α1C specific compounds to treat benign prostatic hyperplasia

ABSTRACT

This invention provides a method of treating benign prostatic hyperplasia in a subject which comprises administering to the subject a therapeutically effective amount of an α 1C  antagonist which (a) binds to a human α 1C  adrenergic receptor with a binding affinity greater than 100-fold higher than the binding affinity with which the α 1C  antagonist binds to a human α 1A  adrenergic receptor, a human α 1B  adrenergic receptor, and a human histamine H 1  receptor; and (b) binds to a human α 2  adrenergic receptor with a binding affinity which is greater than 100-fold lower than the binding affinity with which the α 1C  antagonist binds to such α 1C  adrenergic receptor. 
     The invention further provides a method of inhibiting contraction of a prostate tissue which comprises contacting the prostate tissue with an effective contraction-inhibiting amount of an α 1C  antagonist which (a) binds to a human α 1C  adrenergic receptor with a binding affinity greater than 100-fold higher than the binding affinity with which the α 1C  antagonist binds to a human α 1A  adrenergic receptor, a human α 1B  adrenergic receptor, and a human histamine H 1  receptor; and (b) binds to a human α 2  adrenergic receptor with a binding affinity which is greater than 100-fold lower than the binding affinity with which the α 1C  antagonist binds to such α 1C  adrenergic receptor.

This application is a 371 national stage filing of PCT/US95/04203, filed Apr. 4, 1995, which is a CIP of 08/228,932, filed Apr. 13, 1994, now U.S. Pat. No. 5,578,611, the contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

Benign Prostatic Hyperplasia (BPH), also called Benign Prostatic Hypertrophy, is a progressive condition which is characterized by a nodular enlargement of prostatic tissue resulting in obstruction of the urethra. This results in increased frequency of urination, nocturia, a poor urine stream and hesitancy or delay in starting the urine flow. Chronic consequences of BPH can include hypertrophy of bladder smooth muscle, a decompensated bladder and an increased incidence of urinary tract infection. The specific biochemical, histological and pharmacological properties of the prostate adenoma leading to the bladder outlet obstruction are not yet known. However, the development of BPH is considered to be an inescapable phenomenon for the aging male population. BPH is observed in approximately 70% of males over the age of 70. Currently, in the United States, the method of choice for treating BPH is surgery (Lepor, H., Urol. Clinics North Amer., 17, 651 (1990)). Over 400,000 prostatectomies are performed annually (data from 1986). A medicinal alternative to surgery is clearly very desirable. The limitations of surgery for treating BPH include the morbidity rate of an operative procedure in elderly men, persistence or recurrence of obstructive and irritative symptoms, as well as the significant cost of surgery. α-Adrenergic receptors are specific neuroreceptor proteins located in the peripheral and central nervous systems on tissues throughout the body. These receptors are important switches for controlling many physiological functions and, thus, represent important targets for drug development. In fact, many α-adrenergic drugs have been developed over the past 40 years. Examples include clonidine, phenoxybenzamine and prazosin (treatment of hypertension), naphazoline (nasal decongestant), and apraclonidine (treating glaucoma). α-Adrenergic drugs can be broken down into two distinct classes: agonists (clonidine and naphazoline are agonists), which mimic the receptor activation properties of the endogenous neurotransmitter norepinephrine, and antagonists (phenoxybenzamine and prazosin are antagonists), which act to block the effects of norepinephrine. Many of these drugs are effective but also produce unwanted side effects (for example, clonidine produces dry mouth and sedation in addition to its antihypertensive effects).

During the past 15 years a more precise understanding of α-adrenergic receptors and their drugs has evolved through increased scientific scrutiny. Prior to 1977, only one α-adrenergic receptor was known to exist. Between 1977 and 1988, it was accepted by the scientific community that at least two α-adrenergic receptors--α₁ and α₂ --existed in the central and peripheral nervous systems. Since 1988, new techniques in molecular biology have led to the identification of at least six α-adrenergic receptors which exist throughout the central and peripheral nervous systems: α_(1A), α_(1B), α_(1C), α_(2A), α_(2B) and α_(2C) (Bylund, D. B., FASEB J., 6, 832 (1992)). It is not known precisely which physiological responses in the body are controlled by each of these receptors. In addition, many α-adrenergic drugs that were developed before 1992 are not selective for any particular α-adrenergic receptor. Many of these drugs produce untoward side effects which may be attributed to their poor α-adrenergic receptor selectivity.

Since the mid 1970's, nonselective α-antagonists have been prescribed to treat BPH. In 1976, M. Caine, et al. (Brit. J. Urol., 48, 255 (1976)), reported that the nonselective α-antagonist phenoxybenzamine was useful in relieving the symptoms of BPH. This drug may produce its effects by interacting with α-receptors located on the prostate. However, this drug also produces significant side effects which severely limit its use in treating patients on a chronic basis. More recently, the α-adrenergic antagonists prazosin and terazosin have also been found to be useful for treating BPH. However, these drugs also produce untoward side effects. The most recently approved drug Proscar™ (Merck) prescribed for BPH is not an α-adrenergic antagonist, but rather acts by blocking 5-α-reductase. While Proscar is able to relieve symptoms, it is effective in only 30% of all patients, and requires a period of up to 6 months to show results.

From binding studies using cloned rat α_(1A), hamster α_(1B), and bovine α_(1C) receptors, and functional studies of antagonism in vitro using human prostrate, I. Marshall, et al., concluded that the receptor mediating contraction of the human prostrate is of the α_(1C) subtype (Marshall, I., et al., Brit. Pharmacol. Soc., (1992)).

Furthermore, using cloned human receptors the binding characteristics of the known BPH drugs to various receptor subtypes have been determined, as described more fully hereinafter. Based upon such binding information and additional data, it has been observed that the side effects which occur with the drugs prazosin and terazosin may be due to their poor selectivity for specific α-adrenergic receptors. In contrast, indoramin is a drug which is slightly selective for the human α_(1C) receptor relative to the other human α-adrenergic receptors, but it also interacts at human histamine H1 receptors. This compound produces untoward side effects which may be attributed to its activity at such H₁ receptors.

It would be desirable to provide methods and compounds which allow the treatment of BPH but which avoid the production of side effects observed for all currently used medications.

From the binding information described hereinafter, it has unexpectedly been discovered that compounds which are specific for an α_(1C) adrenergic receptor with a binding affinity greater than ten-fold higher than the binding affinity with which the compounds bind to an α_(1A) adrenergic receptor, a human α_(1B) adrenergic receptor, and a human histamine H₁ receptor, and (b) bind to an α₂ adrenergic receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the compounds bind to such α_(1C) adrenergic receptor are effective for the treatment of BPH.

Furthermore, we have characterized several antagonists selective for the α_(1C) adrenergic receptor using a rat orthostatic hypotension model to ascertain the vascular effects of drugs which may be indicative of their ability to produce dizziness in patients, and observed that while nonselective alpha 1 antagonists produce significant effects on orthostatic hypotension, selective alpha 1c antagonists do not produce significant effects.

SUMMARY OF THE INVENTION

The subject invention provides a method of treating benign prostatic hyperplasia or inhibiting contraction of a prostate tissue in a subject in need thereof which comprises administering to the subject a therapeutically effective amount of an α_(1C) antagonist which binds to a human α_(1c) adrenergic receptor with a binding affinity greater than 50-fold higher than the binding affinity with which the α_(1C) antagonist binds to a human α_(1b) adrenergic receptor, provided that the α_(1C) antagonist is not 2,6-Dimethyl-4-(4-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid N-[3-(4,4-diphenylpiperdin-1-yl)propyl] amide ester hydrochloride hydrate.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1

FIG. 1 illustrates compounds which are potent antagonists of the cloned human α_(1C) receptor.

FIG. 2

Panel A illustrates the correlation of inhibition constants (pK_(i)) for a series of α₁ antagonists at the cloned human α_(1A) receptors with efficiency of blocking contraction of human prostate tissue (pA₂).

Panel B illustrates the correlation of inhibition constants (pK₁) for a series of α, antagonists at the cloned human α_(1B) receptors with efficiency of blocking contraction of human prostate tissue (pA₂).

Panel C illustrates the correlation of inhibition constants (pK₁) for a series of α₁ antagonists at the cloned human α_(1C) receptors with efficiency of blocking contraction of human prostate tissue (pA₂).

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a method of treating benign prostatic hyperplasia or inhibiting contraction of a prostate tissue in a subject in need thereof which comprises administering to the subject a therapeutically effective amount of an α_(1C) antagonist which binds to a human α_(1c) adrenergic receptor with a binding affinity greater than 50-fold higher than the binding affinity with which the α_(1C) antagonist binds to a human α_(1b) adrenergic receptor, provided that the α_(1C) antagonist is not 2,6-Dimethyl-4-(4-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid N-[3-(4,4-diphenylpiperdin-1-yl)propyl] amide ester hydrochloride hydrate.

In a preferred embodiment, the α_(1C) antagonist used to practice the method of the invention additionally binds to a human α_(1a) adrenergic receptor, a human α₂ adrenergic receptor and a human histamine H₁ receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1c) adrenergic receptor.

Desirably, the α_(1C) antagonist used to practice the method of the invention additional binds to the human α_(1c) adrenergic receptor with a binding affinity greater than 75-fold higher than the binding affinity with which the α_(1C) antagonist binds to the human α_(1b) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a human α_(1a) adrenergic receptor, a human α₂ adrenergic receptor and a human histamine H₁ receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1c) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a calcium channel with a binding affinity which is greater than ten-fold lower than the binding affinity with which the α_(1c) antagonist binds to the α_(1c) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a human dopamine D₂ or human histamine H₂ receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to any serotonin receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a dopamine D₃, D₄ or D₅ receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

In one embodiment, the α_(1C) antagonist used to practice the method of the invention additionally does not cause a fall in blood pressure at dosages effective to alleviate benign prostatic hyperplasia or contraction of the prostate tissue.

In a preferred embodiment the α_(1C) antagonist used to practice the method of the invention additionally does not cause a fall in blood pressure in rats at a dosage of 10 micrograms of α_(1C) antagonist per kilogram per rat.

A preferred embodiment the invention provides for a method of treating benign prostatic hyperplasia or inhibiting contraction of prostate tissue in a subject in need thereof which comprises administering to the subject a therapeutically effective amount of an α_(1C) antagonist which binds to a human α_(1c) adrenergic receptor with a binding affinity greater than 100-fold higher than the binding affinity with which the α_(1C) antagonist binds to a human α_(1b) adrenergic receptor and a human histamine H₁ receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a human α_(1a) adrenergic receptor and a human α₂ adrenergic receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1c) adrenergic receptor.

Desirably, the α_(1C) antagonist used to practice the method of the invention additional binds to a calcium channel with a binding affinity which is greater than ten-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a human dopamine D₂ or human histamine H₂ receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to any serotonin receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a dopamine D₃, D₄ or D₅ receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

In one embodiment, the α_(1C) antagonist used to practice the method of the invention additionally does not cause a fall in blood pressure at dosages effective to alleviate benign prostatic hyperplasia or contraction of the prostate tissue.

In a preferred embodiment the α_(1C) antagonist used to practice the method of the invention additionally does not cause a fall in blood pressure in rats at a dosage of micrograms of α_(1C) antagonist per kilogram per rat.

In a preferred embodiment the invention provides for a method of treating benign prostatic hyperplasia in a subject which comprises administering to the subject a therapeutically effective amount of an α_(1C) antagonist which:

a. binds to a human α_(1C) adrenergic receptor with a binding affinity greater than 100-fold higher than the binding affinity with which the α_(1C) antagonist binds to a human α_(1A) adrenergic receptor, a human α_(1B) adrenergic receptor, and a human histamine H₁ receptor; and

b. binds to a human α₂ adrenergic receptor with a binding affinity which is greater than 100-fold lower than the binding affinity with which the α_(1C) antagonist binds to such α_(1C) adrenergic receptor.

In a preferred embodiment of the invention provides for a method of inhibiting contraction of a prostate tissue which comprises contacting the prostate tissue with an effective contraction-inhibiting amount of an α_(1C) antagonist which:

a. binds to a human α_(1C) adrenergic receptor with a binding affinity greater than 100-fold higher than the binding affinity with which the α_(1C) antagonist binds to a human α_(1A) adrenergic receptor, a human α_(1B) adrenergic receptor, and a human histamine H₁ receptor; and

b. binds to a human α₂ adrenergic receptor with a binding affinity which is greater than 100-fold lower than the binding affinity with which the α_(1C) antagonist binds to such α_(1C) adrenergic receptor.

Another embodiment of the inventions provides for a method of inhibiting contraction of a prostate tissue in a subject which comprises administering to the subject an effective contraction-inhibiting amount of an α_(1C) antagonist which:

a. binds to a human α_(1C) adrenergic receptor with a binding affinity greater than 100-fold higher than the binding affinity with which the α_(1C) antagonist binds to a human α_(1A) adrenergic receptor, a human α_(1B) adrenergic receptor, and a human histamine H₁ receptor; and

b. binds to a human α₂ adrenergic receptor with a binding affinity which is greater than 100-fold lower than the binding affinity with which the α_(1C) antagonist binds to such α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally (a) binds to a human α_(1C) adrenergic receptor with a binding affinity greater than 300-fold higher than the binding affinity with which the α_(1C) antagonist binds to a human α_(1A) adrenergic receptor, a human α_(1B) adrenergic receptor, and a human histamine H₁ receptor, and (b) binds to a human α₂ adrenergic receptor with a binding affinity which is greater than 300-fold lower than the binding affinity with which the α_(1C) antagonist binds to such α_(1C) adrenergic receptor.

Desirably, the α_(1C) antagonist used to practice the method of the invention additional binds to a calcium channel with a binding affinity which is greater than ten-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

In one embodiment, the α_(1C) antagonist used to practice the method of the invention additionally binds to a calcium channel with a binding affinity which is greater than 20-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

In a more preferred embodiment, the α_(1C) antagonist used to practice the method of the invention additionally binds to a calcium channel with a binding affinity which is greater than 50-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a calcium channel with a binding affinity which is greater than 100-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a calcium channel with a binding affinity which is greater than 300-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a human dopamine D₂ or human histamine H₂ receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a human dopamine D₂ or human histamine H₂ receptor with a binding affinity which is greater than 20-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a human dopamine D₂ or human histamine H₂ receptor with a binding affinity which is greater than 50-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a human dopamine D₂ or human histamine H₂ receptor with a binding affinity which is greater than 100-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a human dopamine D₂ or human histamine H₂ receptor with a binding affinity which is greater than 300-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Desirably, the α_(1C) antagonist used to practice the method of the invention additionally binds to any serotonin receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to any serotonin receptor with a binding affinity which is greater than 20-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to any serotonin receptor with a binding affinity which is greater than 50-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to any serotonin receptor with a binding affinity which is greater than 100-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the aic antagonist used to practice the method of the invention additionally binds to any serotonin receptor with a binding affinity which is greater than 300-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a dopamine D₃, D₄, or D₅ receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a dopamine D₃, D₄, or D₅ receptor with a binding affinity which is greater than 20-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a dopamine D₃, D₄, or D₅ receptor with a binding affinity which is greater than 50-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a dopamine D₃, D₄, or D₅ receptor with a binding affinity which is greater than 100-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally binds to a dopamine D₃, D₄, or D₅ receptor with a binding affinity which is greater than 300-fold lower than the binding affinity with which the α_(1C) antagonist binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the α_(1C) antagonist used to practice the method of the invention additionally does not cause a fall in blood pressure at dosages effective to alleviate benign prostatic hyperplasia.

In a preferred embodiment, the α_(1C) antagonist used to practice the method of the invention additionally does not cause a fall in blood pressure in rats at a dosage of 10 micrograms of α_(1C) antagonist per kilogram per rat.

The invention provides for the use of a compound which:

a. binds to a human α_(1C) adrenergic receptor with a binding affinity greater than 100-fold higher than the binding affinity with which the α_(1C) antagonist binds to a human α_(1A) adrenergic receptor, a human α_(1B) adrenergic receptor, and a human histamine H₁ receptor; and

b. binds to a human α₂ adrenergic receptor with a binding affinity which is greater than 100-fold lower than the binding affinity with which the α_(1C) antagonist binds to such α_(1C) adrenergic receptor in the preparation of a medicament for treating begin prostatic hyperplasia or inhibiting contraction of a prostate tissue.

In a preferred embodiment of the invention provides for a drug which is useful for treating benign prostatic hyperplasia or inhibiting contraction of a prostate tissue, the effective ingredient of the drug being an α_(1C) antagonist which:

a. binds to a human α_(1C) adrenergic receptor with a binding affinity greater than 100-fold higher than the binding affinity with which the α_(1C) antagonist binds to a human α_(1A) adrenergic receptor, a human α_(1B) adrenergic receptor, and a human histamine H₁ receptor; and

b. binds to a human α₂ adrenergic receptor with a binding affinity which is greater than 100-fold lower than the binding affinity with which the α_(1C) antagonist binds to such α_(1C) adrenergic receptor.

The present invention provides a method of treating benign prostatic hyperplasia in a subject which comprises administering to the subject a therapeutically effective amount of a compound which (a) binds to a human α_(1C) adrenergic receptor with a binding affinity greater than ten-fold higher than the binding affinity with which the compound binds to a human α_(1A) adrenergic receptor, a human α_(1B) adrenergic receptor, and a human histamine H₁ receptor, and (b) binds to a human α₂ adrenergic receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the compound binds to such α_(1C) adrenergic receptor.

Ten-fold selectivity differences are a minimum, but one skilled in the art will appreciate that compounds can be found that collectively have almost infinitely variable selectivity profiles. Compounds collectively having all possible combinations of selectivities are intended within the scope of this invention, provided that each of these compounds has at least a ten-fold greater selectivity for the α_(1C) receptor over the α_(1A), α_(1B), α₂ and H₂ receptors. For example, compounds useful in the methods of this invention can have at least a 10, 20, 30, 40, 50, 75, 100, 200, 300 or greater fold selectivity for binding to the α_(1C) receptor over binding to the α_(1A),α_(1B), α₂ and H₂ receptors. The compounds useful in the methods of this invention can also have selectivity for the α_(1C) receptor over the α_(1A), α_(1B), α₂ and H₂ receptors, such selectivity having a number-fold between these exemplary integers. Furthermore, these compounds can additionally have selectivity within the ranges described above for binding to the α_(1C) receptor over binding to (1) a calcium channel; and/or (2) a D₂ or H2 receptor; and/or (3) any serotonin receptor; and/or (4) a dopamine D₃, D₄ or D₅ receptor.

In the preferred embodiment, the compound (a) binds to a human α_(1C) adrenergic receptor with a binding affinity greater than 20-, 50-, 100- or 300-fold higher than the binding affinity with which the compound binds to a human α_(1A) adrenergic receptor, a human α_(1B) adrenergic receptor, and a human histamine H₁ receptor, and (b) binds to a human α₂ adrenergic receptor with a binding affinity which is greater than 20-, 50-, 100- or 300-fold lower than the binding affinity with which the compound binds to such α_(1C) adrenergic receptor.

Desirably, the compound used to practice the method of the invention additionally binds to a calcium channel with a binding affinity which is greater than ten-fold lower than the binding affinity with which the compound binds to the α_(1C) adrenergic receptor.

In the preferred embodiment, the compound binds to a calcium channel with a binding affinity which is greater than 20-, 50-, 100- or 300-fold lower than the binding affinity with which the compound binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the compound used to practice the method of the invention additionally binds to a human dopamine D₂ receptor or human H₂ receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the compound binds to the α_(1C) adrenergic receptor.

In the preferred embodiment, the compound binds to a human dopamine D₂ or human H₂ receptor with a binding affinity which is greater than 20-, 50-, 100- or 300-fold lower than the binding affinity with which the compound binds to the α_(1C) adrenergic receptor.

Alternatively or incrementally, the compound used to practice the method of the invention additionally binds to any serotonin receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the compound binds to the α_(1C) adrenergic receptor.

In the preferred embodiment, the compound binds to any serotonin receptor with a binding affinity which is greater than 20-, 50-, 100- or 300-fold lower than the binding affinity with which the compound binds to the α_(1C) adrenergic receptor.

Alternatively of incrementally, the compound used to practice the method of the invention also binds to a human dopamine D₃, D₄ or D₅ receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the compound binds to the α_(1C) adrenergic receptor.

In the preferred embodiment, the compound binds to a dopamine D₃, D₄, or D₅ receptor with a binding affinity which is greater than 20-, 50-, 100- or 300-fold lower than the binding affinity with which the compound binds to the α_(1C) adrenergic receptor

Alternatively or incrementally, the compound used to practice the method of the invention also does not cause orthostatic fall in blood pressure at a dosage effective to alleviate benign prostatic hyperplasia or inhibiting contraction of prostate tissue.

In one embodiment, the compound used to practice the method of the invention also does not cause orthostatic fall in blood pressure in rats at a dosage 10 ug/kg.

A number of compounds have been identified or synthesized which are useful in the practice of the invention. For example, the compound has the structure: ##STR1##

In another example, the compound has the structure: ##STR2##

In still another example, the compound has the structure: ##STR3##

In an additional example, the compound has the structure: ##STR4##

Included within the scope of the method of treating BPH in accordance with the invention are the use of both R and S enantiomers of the compounds described which possess stereogenic centers, as well as the use of pharmaceutically acceptable salts and complexes thereof.

The invention also provides a method of inhibiting contraction of prostate tissue which comprises contacting the prostate tissue with an effective contraction-inhibiting amount of a compound which (a) binds to a human α_(1C) adrenergic receptor with a binding affinity greater than ten-fold higher than the binding affinity with which the compound binds to a human α_(1A) adrenergic receptor, a human α_(1B) adrenergic receptor, and a human histamine H₁ receptor, and (b) binds to a human α₂ adrenergic receptor with a binding affinity which is greater than ten-fold lower than the binding affinity with which the compound binds to such α_(1C) adrenergic receptor.

In the preferred embodiment, the compound (a) binds to a human α_(1C) adrenergic receptor with a binding affinity greater than 20-, 50-, 100- or 300-fold higher than the binding affinity with which the compound binds to a human α_(1A) adrenergic receptor, a human α_(1B) adrenergic receptor, and a human H₁ receptor, and (b) binds to a human α₂ adrenergic receptor with a binding affinity which is greater than 20-, 50-, 100- or 300-fold lower than the binding affinity with which the compound binds to such α_(1C) adrenergic receptor.

The activity of compounds at the different human receptors was determined in vitro using cultured cell lines that selectively express the receptor of interest. These cell lines were prepared by transfecting the cloned cDNA or cloned genomic DNA or constructs containing both genomic DNA and cDNA encoding the human α-adrenergic, serotonin, histamine, and dopamine receptors as further described in detail in Example 10 hereinbelow.

In connection with this invention, a number of cloned human receptors discussed herein, either as plasmids or as stably transfected cell lines, have been made pursuant to, and in satisfaction of, the Budapest Treaty on the International Recognition of the Deposit of Microorganisms for the Purpose of Patent Procedure, and are made with the American Type Culture Collection, 12301 Parklawn Drive, Rockville, Md. 20852. Specifically, these deposits have been accorded ATCC Accession Numbers as follows:

    ______________________________________                                         Designation                                                                               ATCC Accession No.                                                                           Date                                                  ______________________________________                                         L-α.sub.1A                                                                          CRL 11138     September 25, 1992                                    L-α.sub.1B                                                                          CRL 11139     September 25, 1992                                    L-α.sub.1C                                                                          CRL 11140     September 25, 1992                                    L-α.sub.2A                                                                          CRL 11180     November 6, 1992                                      L-NGC-α.sub.2B                                                                      CRL 10275     October 25, 1989                                      L-α.sub.2C                                                                          CRL 11181     November 6, 1992                                      pcEXV-H.sub.1                                                                             75346         November 6, 1992                                      pcEXV-H.sub.2                                                                             75345         November 6, 1992                                      pcEXV-D.sub.2                                                                             75344         November 6, 1992                                      ______________________________________                                    

The data shown in the accompanying Tables indicate that the α_(1C) -specific receptor antagonists which satisfy the criteria as defined herein have significant efficacy in the inhibition of contraction of human prostate tissue. This in vitro property is recognized in the art as correlating with efficacy in treating benign prostatic hyperplasia in vivo.

The present invention therefore provides a method of treating benign prostatic hyperplasia, which comprises administering a quantity of any of the α_(1C) receptor antagonists defined as herein in a quantity effective against BPH. The drug may be administered to a patient afflicted with benign prostatic hyperplasia by any conventional route of administration, including, but not limited to, intravenous, intramuscular, oral, subcutaneous, intratumoral, intradermal, and parenteral. The quantity effective against BPH is between 0.001 mg and 10.0 mg per kg of subject body weight.

The method of treating BPH disclosed in the present invention may also be carried out using a pharmaceutical composition comprising any of the α_(1C) receptor antagonists as defined herein and a pharmaceutically acceptable carrier. The composition may contain between 0.05 mg and 500 mg of an α_(1C) receptor antagonist, and may be constituted into any form suitable for the mode of administration selected. Compositions suitable for oral administration include solid forms, such as pills, capsules, granules, tablets, and powders, and liquid forms, such as solutions, syrups, elixirs, and suspensions. Forms useful for parenteral administration include sterile solutions, emulsions, and suspensions.

The drug may otherwise be prepared as a sterile solid composition which may be dissolved or suspended at the time of administration using sterile water, saline, or other appropriate sterile injectable medium. Carriers are intended to include necessary and inert binders, suspending agents, lubricants, flavorants, sweeteners, preservatives, dyes, and coatings.

Optimal dosages to be administered may be readily determined by those skilled in the art, and will vary with the particular α_(1C) receptor antagonist in use, the strength of the preparation, the mode of administration, and the advancement of the disease condition. Additional factors depending on the particular patient being treated will result in a need to adjust dosages, including patient age, weight, diet, and time of administration.

The term "therapeutically effective amount" as used herein means that amount of active agonist or pharmaceutical agent that elicits the biological or medicinal response in a tissue, system, animal or human that is being sought by a researcher, veterinarian, medical doctor or other clinician, which includes alleviation of the symptoms of the disease being treated.

The term "subject," as used herein refers to an animal, preferably a mammal, most preferably a human, who has been the object of treatment, observation or experiment.

The following Experimental Details are set forth to aid in an understanding of the invention, and are not intended, and should not be construed, to limit in any way the invention set forth in the claims which follow thereafter.

EXPERIMENTAL DETAILS

Prazosin, 5-methylurapidil, and S-niguldipine were obtained from Research Biochemicals, Inc. A30360 (4-fluoro-4-(8-fluoro-1,3,4,5-tetrahydro-2H-pyrido[4,3-b]indol-2-yl)butyrophenone hydrochloride) was obtained from Aldrich Chemical Co. Other compounds were prepared according to the examples which follow.

EXAMPLE 1 Synthesis of Terazosin Hydrochloride

N-(2-Furoyl)piperazine

This compound and its preparation has been described in Great Britain Patents 1,390,014 and 1,390,015. Piperazine hexahydrate (194 g, 1 mole) was dissolved in 250 ml H₂ O. The solution was acidified to pH 4.5 with 6 N HCl. Furoyl chloride (130.5 g, 1 mole, Aldrich) was added along with 10% NaOH solution at such a rate that the pH was maintained at 4.5. After 1 hour, the solution was made basic (pH=8.5) with NaOH solution. The reaction mixture was continuously extracted with chloroform for 36 hours. The CHCl₃ extract was dried over MgSO₄, and filtered. Distillation gave 108.2 g product (60%), b.p. 132°-138° C../0.6 mm Hg, m.p. 69°-70° C..

N-(Tetrahydro-2-furoyl)piperazine

The furoylpiperazine of Example 1 was converted to the hydrobromide salt (m.p. 173°-175° C..). This salt (39.0 g) in 250 ml methyl alcohol and 9.0 g Raney nickel was hydrogenated at 3 atm. After uptake of H₂ ceased, the catalyst was filtered, the solvent concentrated, and the residue crystallized from isopropyl alcohol to give 35.2 g. tetrahydrofuroylpiperazine HBr, m.p. 152°-156° C.. This was suspended in 20 ml H₂ O. Then 10.5 g 50%, NaOH solution was added slowly followed by 2.0 g solid Na₂ CO₃. This was extracted with 4×100 ml portions of warm CHCl₃. The CHCl₃ extractions were distilled to give 22.5 g tetrahydrofurolylpiperazine, b.p. 120°-125° C../0.2 mm Hg.

2-[4-(Tetrahydro-2-furoyl)piperazinyl]-4-amino-6,7-dimethoxyquinazoline hydrochloride

To 7.00 g 2-chloro-4-amino-6,7-dimethoxyquinazoline (Lancaster Synthesis) in 50 ml methoxyethanol was added 10.8 g, tetrahydrofurolylpiperazine, and the mixture refluxed 3 hours. The clear solution was concentrated and an aqueous solution of potassium bicarbonate was added. The resultant solid that formed was filtered and washed with water. It was then added to methanol and the resulting suspension was acidified with a solution of hydrogen chloride in isopropyl alcohol. The resulting solution was concentrated and the residue crystallized from isopropyl alcohol giving 8.12 g. of product, m.p. 278°-279° C..

EXAMPLE 2 Preparation of Indoramin

4-Benzamido-1-[2-(3-indolyl)ethylpyridinium Bromide

A solution of 4-benzamidopyridine (1.98 g) and 3-(2-bromoethyl)indole (2.24 g) in EtOH (15 ml) was refluxed for 2 hours, and the crystallized product (3.13 g, mp 264-266° C..) was collected by filtration from the hot reaction mixture. Recyrstallization gave the hydrate.

3-[2-4-Benzamidopiperid-1-yl)ethyl]indole (Indoramin)

4-Benzamido-1-[2-(3-indolyl)ethyl]pyridinium bromide (3.0g) in 91% EtOH (300 ml) containing Et₃ N (0.8 g) was hydrogenated in the presence of freshly prepared W-7 Raney Ni catalyst (ca. 3 g) at 28.12 kg/cm² and 50° for 4 hours. After filtering off the catalyst, the filtrate was evaporated and the residue was shaken with CHCl₃ and 2 N NaOH. The resulting insoluble material (1.61 g, mp 203-206° C..) was collected and dried. Recrystallization from EtOH gave the product (1.34 g), as colorless needles.

EXAMPLE 3

Preparation of 1-(3-benzoylpropyl)-4-benzamidopiperidine

A mixture of 4-chlorobutyrophenone (447 mg, 2.45 mmol), 4-benzamidopiperidine (500 mg, 2.45 mmol) and K₂ CO₃ (338 mg, 2.45 mmol) was heated up in boiling water bath for 1 hour. The reaction mixture was portioned between water and CHCl₃. The organic layer was separated and dried over Na₂ SO₄. After filtration and removal of solvent, the residue was purified by chromatography (SiO₂, MeOH:CHCl₃, 5:95). Recrystallization from AcOEt/hexane gave a white powder (78 mg, 8.2%). mp 143-144° C..; ¹ H NMR (CD₃ OD, 400 MHz) δ 1.65 (dq, J₁ =3.16 Hz, J₂ =11.9 Hz, 2H), 1.90-2.00 (m, 4H), 2.18 (t, J=11.9 Hz, 2H), 2.48 (m, 2H), 3.00-3.10 (m, 4H), 3.88 (m, 1H), 7.40-8.00 (m, 10H); Mass spectrum (M+1)⁺ at m/z 351.

EXAMPLE 4

Preparation of 1-[3-(4-chlorobenzoyl)propyl]-4-benzamidopiperidine

A mixture of 3-(4-chlorobenzol)propyl bromide (640 mg, 2.45 mmol), 4-benzamidopiperidine (500 mg, 2.45 mmol) and K₂ CO₃ (1.01 g, 7.34 mmol) in 50 ml of acetone was heated up to refluxing condition for 48 hours. The solid was removed by filtration. Concentration of filtrate in vacuo gave a yellowish solid, which was purified by chromatography (SiO₂, MeOH:CHCl₃, 5:95). 320 mg (33.9%) of white powder was obtained ¹ H NMR (CDCl₃, 300 mHz) δ 1.46 (dq, J₁ =1.0 Hz, J₂ =8.4 Hz, 2H), 1.90-2.10 (m, 4H), 2.16 (m, 2H), 2.43 (t, J=6.9 Hz, 2H), 2.80-2.90 (m, 2H), 2.97 (t, J=6.9 Hz, 2H), 3.97 (m, 1H), 5.92 (d, J=7.8 Hz, 1H, N-H), 7.40-8.00 (m, 9H); Product was converted to HCl salt and recrystallized with MeOH/Et₂ O, mp 243-244° C..; Calcd for C₂₂ H₂₅ ClN₂ O₂.HCl.H₂ O: C 60.15, H 6.37, N 6.37; Found: C 60.18, H 6.34, N6.29.

EXAMPLE 5 Preparation of SKF-104856

1-[(4-Chlorophenyl)thio}-2-propanone

Chloroacetone (32.3 g, 0.347 mol) was added to a mixture of 4-chlorothiophenol (50 g, 0.347 mmol) and sodium hydroxide (14 g, 0.347 mol) in water (400 ml) and the mixture was stirred at 25° C.. for 1 hour. The mixture was extracted with ethyl ether and the organic phase was washed with water, dried with magnesium sulfate and concentrated to give 69 g (99%) of 1-[(4-chlorophenyl)thio]-2-propanone.

5-Chloro-3-methylbenzo(b)thiophene

1-[(4-Chlorophenyl)thio}-2-propanone (50 g, 0.25 mol) was added to polyphosphoric acid (300 g) and the mixture was stirred as the temperature was gradually raised to 120° C.. as an exotherm started. The mixture was stirred at 130° C.. for 1 hour, diluted with water, extracted with ethyl ether and the organic phase was dried and concentrated. The residue was stirred in methanol (200 ml), filtered and the filtrate concentrated to give 17.5 g (40%) of 5-chloro-3-methylbenzo(b)thiophene: bp 120° C.. (0.6 mm Hg).

Ethyl 5-chloro-3-methylbenzo(b)thiophene-2-carboxylate

n-Butyllithium in hexane (2.6 M, 2.3 ml) was added to a solution of 5-chloro-3-methylbenzo(b)thiophene (1,0 g, 6 mmol) in ethyl ether (20 ml) stirred at 0° C.. under argon. The mixture was stirred for 30 minutes and transferred slowly under argon pressure to a stirred solution of ethyl chloroformate (0.63 g, 6 mmol) in ethyl ether (20 ml). The mixture was stirred at 0° C.. for 30 minutes and at 25° C.. for 1.5 hours. The mixture was treated with water and the organic phase was dried, concentrated and triturated with hexane to give 1.0 g (67w) of ethyl 5-chloro-3-methylbenzo(b)thiophene-2-carboxylate: mp 92.5-94° C..

Ethyl 3-bromomethyl-5-chlorobenzo(b)thiophene-2-carboxylate

A mixture of ethyl 5-chloro-3-methylbenzo(b)thiophene-2-carboxylate (9.0 g, 0.035 mol), N-bromosuccinimide (6.53 g, 0.037 mol) and benzoyl peroxide (130 mg) in carbon tetrachloride (150 ml) was refluxed and illuminated with sunlamp for 2 hours. The resulting suspension was cooled, filtered and the filter cake was triturated with methanol to give 9.9 g, (85%) of the methanol-insoluble ethyl 3-bromomethyl-5-chlorobenzo(b)thiophene-2-carboxylate: mp 148-150° C..

Ethyl 5-Chloro-3-[N-(2,2-dimethoxyethyl)-N-methyl(aminomethyl)]benzol(b)thiophene-2-carboxylate

A mixture of ethyl 3-bromomethyl-5-chlorobenzo(b)thiophene-2-carboxylate (11 g, 0.033 mol), methylaminoacetaldehyde dimethyl acetal (4.76 g, 0.04 mol) and potassium carbonate (11.4 g, 0.8 mol) in dry acetone (200 ml) was stirred for 48 hours, filtered and the filtrate concentrated to give 11.8 g, (96%) of ethyl 5-chloro-3-(N-2,2-dimethoxyethyl)-N-methyl(aminomethyl)benzol(b)thiophene-2-carboxylate.

Ethyl 7-chloro-3,4-dihydro-4-methylthieno[4,3,2-ef][3]benzazepine-2-carboxylate

Ethyl 5-chloro-3-[N-(2,2-dimethoxyethyl)-N-methyl(aminomethyl)]benzo[b]thiophene-2-carboxylate (3.0 g, 8.1 mmol) was added in portions to trifluoromethanesulfonic acid (10 ml) stirred at 0° C.. under argon. The mixture was stirred at 25° C.. for 45 minutes and diluted with water. The mixture was basified with aqueous sodium hydroxide and extracted with ethyl ether to give ethyl 7-chloro-3,4-dihydro-4-methylthieno-[4,3,2-ef][3]benzazepine-2-carboxylate

Ethyl 7-chloro-3,4,5,6-tetrahydro-4-methylthieno[4,3,2-ef][3]benzazepine-2-carboxylate

Diborane in tetrahydrofuaran (1 M, 40 ml) was added to a solution of ethyl 7-chloro-3,4-dihydro-4-methylthieno-[4,3,2-ef][3]benzazepine-2-carboxylate (2.8 g) in tetrahydrofuran (30 ml) stirred at 0° C.. The mixture was refluxed for 3 hours and stirred at 25 C. for 18 hours, cooled, treated with methanol (50 ml), refluxed for 18 hours and concentrated. The residue was triturated with ethyl ether-hexane (3:1) to give 1.6 g (84) of ethyl 7-chloro-3,4,5,6-tetrahydro-4-methylthieno[4,3,2-ef][3]benzazepine-2-carboxylate: mp 138-140° C.. The free base was treated with hydrogen chloride to give ethyl 7-chloro-3,4,5,6-tetrahydro-4-methylthieno[4,3,2-ef][3]benzazepine-2-carboxylate hydrochloride: mp 240° C..

7-Chloro-3,4,5,6-tetrahydro-4-methylthieno[4,3,2-ef][3]benzazepine-2-methanol

A solution of ethyl 7-chloro-3,4,5,6-tetrahydro-4-methylthieno[4.3.2-ef][3]benzazepine-2-carboxylate (4.0 g, 12.9 mmol), in ethyl ether (48 ml) was treated with lithium aluminum hydride (0.53 g, 14 mmol). The mixture was stirred for 1.5 hours, cooled and treated carefully with water (2.0 ml), 10% sodium hydroxide (1.0 ml) and water (2.0 ml). The resulting mixture was filtered and the solvent evaporated to give 1.9 g (57%) of 7-chloro-3,4,5,6-tetrahydro-4-methylthieno[4,3,2-ef][3]benzazepine-2-methanol: mp 184-185° C..

7-Chloro-3,4,5,6-tetrahydro-4-methylthieno-4,3,2-ef][3]benzazepine-2-carboxaldehyde

A solution of 7-chloro-3,4,5,6-tetrahydro-4-methylthieno[4,3,2-ef][3]benzazepine-2-methanol (1.6 g, 6 mmol) in dichloromethane (150 ml) was stirred under argon with activated manganese dioxide (8.3 g) for 2 hours. The mixture was filtered through Celite™ and the filtrate was dried with magnesium sulfate and concentrated to give a 63% yield of 7-chloro-3,4,5,6-tetrahydro-4-methylthieno[4,3,2-ef[[3]benzazepine-2-carboxaldehyde.

7-Chloro-2-ethenyl-3,4,5,6-tetrahdyro-4-methylthieno-[4,3,2-ef][3]benzazepine (SKF-104856)

Sodium hydride (60 %o dispersion in mineral oil. 3.8 mmol) was added to a stirred solution of methyltriphenylphosphonium bromide (1.35 g, 3.8 mmol) in dry tetrahydrofuran (30 ml) and stirred for 15 minutes. The mixture was treated with a solution of 7-chloro-3,4,5,6-tetrahydro-4-methylthieno[4,3,2-ef][3]-benzazepine-2-carboxaldehyde, prepared as in Example 3, (0.5 g, 1.9 mmol) in dimethyl-formamide (4 ml), stirred at 25° C.. for 16 hours, quenched with ice and extracted with ethyl acetate. The organic phase was washed, dried and concentrated and the residue was chromatographed on silica gel eluted with a gradient of methylene chloride to methanol-methylene chloride (3.5:96.5). The product was treated with hydrogen chloride to give 0.2 g (35%) of 7-chloro-2-ethenyl-3,4,5,6-tetrahydro-4-methylthieno-[4,3,2-ef][3]benzazepine hydrochloride: mp 234-236° C..

EXAMPLE 6

2-Hydroxymethyl-1,2,3,4-tetrahydronaphthalene

A solution of 1,2,3,4-tetrahydro-2-naphthoic acid (2.50 g, 14.2 mmol) in 100 ml THF was treated with LiAlH₄ (681 mg, 17.04 mmol) and the reaction mixture was heated at reflux for 5 hours. The suspension was cooled to 0° C.. and quenched by addition of solid Na₂ SO₄ ▪10H₂ O. The mixture was stirred at room temperature for 4 hours. The solid was removed by filtration. Concentration of filtrate in vacuo gave a yellowish oil (2.28 g, 98.8%); ¹ H NMR (CDCl₃, 300 MHz) δ 1.43 (m, 1H), 2.00 (m, 2H) 2.51 (dd, J₁ =16.5 Hz, J₂ =10.8 Hz, 1H), 2.85 (m, 3H), 3.65 (dd, J₁ =6.3 Hz, J₂ =1.2 Hz, 2H), 7.09 (s, 4H).

2-Bromomethyl-1,2,3,4-tetrahydronaphthalene

A solution of 2-hydroxymethyl-1,2,3,4-tetrahydronaphthalene (2.28 g, 14.0 mmol) in 100 ml of CH₂ Cl₂ was treated with PBr₃ (1.28 g, 4.73 mmol) at 0° C.. The mixture was stirred at room temperature for 72 hours then poured onto 100 g of ice. The organic layer was isolated, washed with 10% K₂ CO₄ aqueous solution, H₂ O, sat'd brine, and then dried over Na₂ SO₄. After filtration and removal of solvent, the residue was purified by chromatography (SiO₂, EtOAc:hexane, 1:10) to give a colorless oil (1.33 g, 41.6%); ¹ H NMR (CDCl₃, 300 MHz) δ 1.55 (m, 1H), 2.11 (m, 1H), 2.11 (m, 2H), 2.58 (dd, J₁ =16.2 Hz, J₂ =10.2 Hz, 1H), 2.80-3.10 (m, 3H), 3.45 (d, J=6.3 Hz, 2H), 7.10 (m, 4H).

2-[(4-Methoxyphenethyl)aminomethyl]-1,2,3,4-tetrahydronaphthalene (Compound 11)

A solution of 2-bromomethyl-1,2,3,4-tetrahydronaphthalene (1.33 g, 5.91 mmol) and 4-methoxyphenethylamine (1.79 g, 11.8 mmol) in 50 ml of EtOH was refluxed for 48 hours. After removal of EtOH in vacuo, the residue was dissolved in 100 ml of CHCl₃, washed with 10% K₂ CO₃, H₂ O, sat'd brine, and then dried over Na₂ SO₄. Filtration followed by evaporation of solvent gave a yellow oil, which was purified by chromatography (SiO₂, MeOH:CHCl₃, 5:95) to a give a yellowish oil (1.03 g, 58.9%). The product was converted to HCl salt, crystallization with MeOH/Et₂ O gave a white powder. mp 274-275° C..; Calcd for C₂₀ H₂₅ NO.HCl: C 72.37, H 7.91, N 4.22; Found C 72.40, H 7.76, N 4.13.

EXAMPLE 7

4,4-Diphenylpiperidine hydrochloride

A mixture of 4-piperidone monohydrate hydrochloride (15.0 g, 97.6 mmol, 1.00 equiv, Aldrich) and AlCl₃ (130 g, 976 mmol, 10.0 equiv) in anhydrous benzene (600 mL) was stirred at reflux for 4 hours. Ice (300 g) and water (50 mL) were added, the mixture was filtered, and the solid was washed with toluene and dried to afford 19.2 g (72%) of off-white solid, which was pure by ¹ H NMR. Recrystallization from ethanol gave the analytically pure sample: m.p. 300-301° C..; ¹ H NMR (300 MHz, CD₃ OD) δ 2.65 (m, 4 H), 3.18 (m, 4 H), 7.18 (m, 2 H), 7.30 (m, 8 H); Anal. Calcd. for C₁₇ H₁₉ N.HCl: C, 74.57; H. 7.36; N, 5.12. Found: C, 74.32; H, 7.34; N, 5.02. The free base was generated by addition of the above salt to dilute aqueous sodium hydroxide and extraction with CH₂ Cl₂. The organic phase was dried over MgSO₄ and concentrated to give a light brown solid: IR (neat) 2942.8, 1494.5, 1445.9 cm⁻¹ ; CIMS (NH₃) m/e 238 (M+1)⁺.

3-(4,4-Diphenylpiperidin-1-yl)propionitrile

To a suspension of 4,4-diphenylpiperidine hydrochloride (195 mg, 0.712 mmol, 1.0 equiv) in ETOh (1.5 mL) was added triethylamine (0.25 mL, 1.83 mmol, 2.6 equiv) followed by acrylonitrile (0.13 mL, 2.01 mmol, 2.8 equiv). The resulting solution was stirred at room temperature under argon for 15 minutes and then concentrated. Water was added, and the mixture was extracted three times with EtOAc. The combined organic extracts were dried over MgSO₄ and concentrated to give 170 mg (87%) of tan solid, which was used for the next reaction without purification. m.p. 95-96° C..; ¹ H NMR (300 MHz, CDCl₃) δ 2.37 (m, 2H), 2,46 (m, 4H), 2.52 (m, 6H), 7.12 (m, 2H), 7.23 (m, 8H); ¹³ C NMR (75 MHz, CDCl₃) δ 16.65, 36.71. 45.08, 50.78, 54.13, 119.70, 126.48, 127.78, 129.11, 147.87; IR (neat) 2944.4, 2821.0, 1495.5, 1445.9 cm⁻¹.

1-(3-Aminopropyl)-4,4-diphenylpiperidine

To a stirred solution of 3-(4,4-diphenylpiperidine-1-yl)propionitrile (2.00 g, 6.89 mmol, 1.0 equiv) in anhydrous THF (20 mL) under argon was added a solution of BH₃ in THF (1.0 M, 24.1 mL, 24 mmol, 3.5 equiv) at room temperature. The mixture was refluxed for 4.5 hours and then cooled to room temperature. Aqueous HCl (6 N, 50 mL) was added and stirring was continued for 1 hour. The mixture was basified to pH 9 by addition of 6 N aq. NaOH, extracted 3 times with CH₂ Cl₂, dried over MgSO₄ and concentrated. The residue was purified by flash chromatography (SiO₂, EtOAc-MeOH, 9:1, followed by EtOAc-MeOH-isopropylamine (60:10:1), followed by EtOAc-MeOH-isopropylamine (40:10:2) to give 1.35 g (66%) of tan solid: m.p. 98-99° C..; ¹ H NMR (300 MHz, CDCl₃) δ 1.64 (tt, J=7.7 Hz, 2H), 2.33 (br t, J=7.2 Hz, 2H), 2.50 (m, 8H), 2.76 (br t, J=6.5 Hz, 2H), 3.06 (br s, 2H), 7.13 (m, 2H), 7.26 (m, 8H); ¹³ C NMR (75 MHz, CDCl₃) δ 29.79, 36.80, 41.41, 45.24, 51.25, 57.41, 126.30, 127.77, 128.97, 148.11; IR (neat) 3361.5 cm⁻¹ ; CIMS (NH₃) m/e 295 (M+1)⁺.

Acetoacetic acid N-13-(4,4-diphenylpiperidin-1-yl)propyl]amide

Diketene (0.44 mL, 5.68 mmol, 1.3 equiv, Aldrich) was added at room temperature to a stirred solution of 1-(3-aminopropyl)-4,4-diphenylpiperidine (1.288 g, 4.37 mmol, 1.0 equiv) in anhydrous toluene (15 mL) under argon, and stirring was continued for 48 hours. The mixture was concentrated to give 1.294 g (78%) of white solid, which was used for the next reaction without purification: ¹ H NMR (300 MHz, CDCl₃) δ 1.70 (tt, J=6.4, 6.4 Hz, 2H), 2.23 (s, 3H), 2.44 (br t, J=6.5 Hz), 2.49-2.67 (m, 8H), 3.32 (br t, J=5.8 Hz), 3.36 (s, 2H), 7.16 (m, 2H), 7.27 (m, 8H).

2,6-Dimethyl-4-(4-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid N-[3-(4,4-diphenylpiperidine-1-yl)propyl]amide methyl ester

A solution of acetoacetic acid N-[3-(4,4-diphenylpiperidin-1-yl)propyl]amide (365 mg, 0.964 mmol, 1.0 equiv), methyl 3-aminocrotonate (138 mg, 1.20 mmol, 1.2 equiv, Aldrich), and 4-nitrobenzaldehyde (181 mg, 1.20 mmol, 1.2 equiv, Aldrich) in isopropanol was refluxed under argon for 60 hours. The mixture was cooled to room temperature and concentrated, and the residue was diluted with CH₂ Cl₂, washed with water, dried over MgSO₄, and concentrated. The residue was purified by flash chromatography (SiO₂, EtOAc, followed by EtOAc-MeOH, 19:1 and 9:1) to give 147.8 mg (25%) of yellow solid: ¹ H NMR (300 MHz, CDCl₃) δ 1.55 (m, 2H), 2.14 (s, 3H), 2.15-2.50 (m, 10H), 2.32 (s, 3H), 3.20 (m, 1H), 3.37 (m, 1H), 3.54 (s, 3H), 5.00 (s, 3H), 5.48 (br s), 6.98 (br t, J=4.9 Hz, 1H), 7.14-7.30 (m, 10H), 7.39 (dm, J=8.7 Hz, 2H), 8.05 (dm, J=8.7 Hz, 2H); ¹³ C NMR (75 MHz, CDCl₃) δ 18.74, 20.64, 25.61, 36.77, 40.20, 42.26, 45.03, 51.16, 51.61, 58.08, 100.65, 109.71, 124.35, 126.46, 127.61, 128.84, 129.06, 135.52, 146.96, 147.10, 154.55, 168.22, 168.70; IR (neat) 1680, 1610, 1515, 1340 cm⁻¹ ; MS (FAB) m/e 609 (M+H)⁺.

2,6-Dimethyl-4-(4-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid N-[3-(4,4-diphenylpiperidin-1-yl)propyl]amide methyl ester hydrochloride hydrate (Compound 2)

To a solution of 2,6-dimethyl-4-(4-nitrophenyl)-1,4-dihydro-pyridine-3,5-dicarboxylic acid N-[3-(4,4-diphenylpiperidin-1-yl)propyl]amide methyl ester (147.8 mg, 0.243 mmol, 1.0 equiv) in EtOH (2 mL) was added a solution of HCl in ether (1.0 M, 0.24 mL, 0.24 mmol, 1.0 equiv). Addition of ethyl acetate (3 mL) followed by heating gave a clear solution. Slow cooling of this solution, followed by filtration gave 91 mg of yellow crystalline solid: m.p. 182-183° C..; Anal. Calcd. for C₃₆ H₄₀ N₄ O₅.HCl.H₂ O: C, 65.20, H, 6.54; N, 8.45. Found: C, 65.30; H, 6.28; N, 8.15.

EXAMPLE 8

3-(4,4-Diphenylpiperid-1-yl)-propanol

4,4-Diphenylpiperidine (40 g), 3-bromopropanol (24.7 g, Aldrich), powdered potassium carbonate (116.4 g) and approximately 1 g of potassium iodide (in 500 ml of a 1:1 mixture of dioxane and 1-butanol) were heated for about 48 hours under reflux and with vigorous stirring. After cooling, the mixture was filtered, and the filtrate was concentrated. The oily residue was taken up in ethyl acetate, and the solution was filtered again. Concentrating the filtrate to dryness yielded the product in the form of a yellowish, oily residue which slowly solidifies to a wax-like product (yield: 44.8 g). Hydrochloric acid in ether produced the hydrochloride (m.p.: 226° to 2270° C..), which was recrystallized from 2-propanol.

Acetoacetic acid 3-(4,4-diphenylpiperidin-1-yl)propyl ester

23.6 g of 3-(4,4-diphenylpiperid-1-yl)-propanol were dissolved in 100 ml of absolute toluene, and 16 ml of a 50% strength solution of diketene in acetone were added with stirring. After standing for several days at room temperature (monitored by thin layer chromatography), the mixture was concentrated, and the residue was dried under high vacuum. The pale yellow, viscous oil which remains was employed without further purification for the next stage.

2,6-Dimethyl-4-(4-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxy-ylic acid [3-(4,4-diphenylpiperidin-1-yl)propyl] ester methyl ester

A solution of methyl 3-aminocrotonate (265 mg, 2.3 mmol, 1.0 equiv), 4-nitrobenzaldehyde (348 mg, 2.3 mmol, 1.0 equiv), and acetoacetic acid 3-[4,4-diphenylpiperidin-1-yl)propyl] ester (872 mg, 2.3 mmol, 1.0 equiv) in isopropanol was refluxed under argon with stirring for 68 hours. Cooling and removal of solvent gave a residue, which was purified by flash chromatography (SiO₂, EtOAc-hexane, 1:1 and 1:2, followed by EtOAc) to afford 717 mg (51%) of yellow solid: ¹ H NMR (300 MHz, CDCl₃) δ 1.73 (m, 2H), 2.22 (m, 2H), 2.30-2.51 (m, 8H), 2.34 (s, 3H), 2.35 (s, 3H), 3.63 (s, 3H), 4.05 (dt, J=2.1, 7.9 Hz, 2H), 5.06 (s, 1H), 5.73 (br s, 1H), 7.14 (m, 2H), 7.27 (m, 8H), 7.42 (dm, J=8.8 Hz, 2H), 8.06 (dm, J=8.8 Hz, 2H); ¹³ C NMR (75 MHz, CDCl₃) δ 15.30, 19.65, 26.32, 36.11, 39.88, 44.60, 50.60, 51.12, 55.34, 62.66, 102.99, 107.55, 123.39, 125.67, 127.12, 128.33, 128.65, 144.80, 144.93, 146.36, 147.50, 154.78, 166.91, 167.43; IR (neat) 1698.0, 1684.7, 1517.5, 1345.7 cm⁻¹ ; CIMS (NH₃) 610 (M+1)⁺, 553, 338.

2,6-Dimethyl-4-(4-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid [3-(4,4-diphenylpiperidin-1-yl)propyl] ester methyl ester hydrochloride (Compound 8)

To a solution of 2,6-dimethyl-4-(4-nitrophenyl)-1,4-dihydro-pyridine-3,5-dicarboxylic acid [3-(4,4-diphenylpiperidine-1-yl)-propyl] ester methyl ester (710 mg, 1.16 mmol, 1.0 equiv) in EtOH (5 mL) was added a solution of HCl in ether (1.0 M, 1.5 mL, 1.5 mmol, 1.3 equiv). The solvents were removed and the residue was dissolved in CH₂ Cl₂. This solution was added dropwise to 25 mL of ether to afford, after filtration, 500 mg of yellow crystalline solid: m.p. 152-153° C.. Anal. Calcd. for C₃₆ H₃₉ N₃ O₆.HCl: C, 66.92; H, 6.24; N, 6.50. Found: C, 66.70; H, 5.99; N, 6.27

EXAMPLE 9

6-Ethyl-4-(4-nitrophenyl)-2-((2-aminoethyl)oxy)methyl-5-carboxamido-3-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine (Scheme 1).

a. 3-(4,4-Diphenylpiperidin-1-yl)propionitrile. To a suspension of 4,4-diphenylpiperidine hydrochloride (0.195 g, 0.712 mmol) in EtOH (1.5 mL) was added Et₃ N (0.25 mL, 1.8 mmol, 2.6 eq) followed by acrylonitrile (0.13 mL, 2.01 mmol, 2.8 eq). The resulting solution was stirred at room temperature under argon for 15 min and then concentrated. Water was added, and the mixture was extracted with EtOAc (3×10 mL). The combined organic extracts were dried (MgSO₄) and concentrated to give 170 mg (87%) of tan solid, which was characterized spectroscopically and used in the next reaction without purification.

b. 3-(4,4-Diphenylpiperidin-1-yl)propylamine. To a stirred solution of 3-(4,4-diphenylpiperidin-1-yl)propionitrile (2.00 g, 6.89 mmol) in anhydrous rHF (20 mL) under argon was added a solution of BH₃ in THF (1.0 M, 24.1 mL, 24 mmol, 3.5 eq) at room temperature. The mixture was refluxed for 4.5 h and then cooled to room temperature. Aqueous HCl (6 N, 50 mL) was added and stirring was continued for 1 h. The mixture was basified to pH 9 by addition of 6 N aq. NaOH, extracted with CH₂ Cl₂ (3×10 mL), dried (MgSO₄) and concentrated. The residue was purified by flash chromatography (SiO₂, EtOAc-MeOH-isopropylamine 9:1:0 to 4:1:0.2) to give 1.35 g (66%) of tan solid, which was characterized spectroscopically.

c) (±)-6-Ethyl-4-(4-nitrophenyl)-2-(methyloxy)methyl-5 (2-cyanocarboethoxy)-3-(carbophenylmethoxy)-1,4-dihydropyridine: A mixture of 3.28 g of ethyl 4-methoxy-3-oxo-butanoate (20.5 mmol) and 4.43 g of benzyl alcohol (41.0 mmol) were heated at 140-150 ° C.. (10-15) for 2 hrs. The reaction mixture was cooled, diluted with 20 mL of ethanol (denatured), 1.90 g of ammonium acetate (24.6 mmol) was added, and the resulting mixture was heated at reflux temperature for 1.5 hrs. The reaction mixture was cooled and 5.27 g of 2-cyanoethyl 2-(4-nitrobenzilidino)-3-oxopentanoate was added to the reaction mixture. The resulting mixture was heated at reflux temperature for 2 hrs, cooled, and solvent was removed in vacuo. The crude product was chromatographed on 550 g of silica packed with 10% EtOAc-hexane. The column was eluted with 20% (2 L), and 30% EtOAc-hexane (4 L) to give 3.08 g (30%) of 6-ethyl-4-(4-nitrophenyl)-2-(methyloxy)methyl-5-(2-cyanocarboethoxy)-3-(carbophenylmethoxy)-1,4-dihydropyridine as a yellow oil with solidified on standing. The product was used in the next step after pectral characterization.

d) (±)-2-Ethyl-4-(4-nitrophenyl)-6-(methyloxy)methyl-3-(2-cyanocarboethoxy)-1,4-dihydropyridine-3-carboxylic Acid: A suspension of 2.86 g of 6-ethyl-4-(4-nitrophenyl)-2-(methyloxy)methyl-5-(2-cyanocarboethoxy)-3-carbophenylmethoxy)-1,4-dihydropyridine (5.66 mmol), 572 mg of 10% Pd/C, 70 mL of methanol, and 2.09 mL of formic acid were stirred at room temperature for 0.5 h. The reaction mixture was diluted with 30 rnL of chloroform, filtered through a pad of Celite 545. The filtrate was concentrated in vacuo, and the residue was chromatographed on 250 g of silica packed with 30% EtOAc-hexane. The column was eluted with 50% to 80% EtOAc-hexane (10% change/1 L) to give 1.33 g of 2-ethyl-4-(4-nitrophenyl)-6-(methyloxy)methyl-3-(2-cyanocarboethoxy)-1,4-dihydropyridine-3-carboxylic acid (57%) as a yellow oily solid. Anal. Calc. for C₂₀ H₂₁ N₃ O.sub.₇ : C, 57.83; H, 5.10; N, 10.12. Found: C, 57.78; H, 5.08; N, 9.99.

e) (±)-2-Ethyl-4-(4-nitrophenyl)-6-(methyloxy)methyl-3-(2-cyanocarboethoxy)-5-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine, Hemihydrate: A solution of 433 mg of 2-ethyl-4-(4-nitrophenyl)-6-(methoxy)methyl-3-(2-cyanocarboethoxy)-1,4-dihydropyridine-3-carboxylic acid (1.04 mmol), 401 mg of 1-(dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (DMAPECD) (2.09 mmol), and 153 mg of 4-dimethylaminopyridine (DMAP) (1.25 mmol) in 5 mL of dry dichloromethane were stirred at room temperature for 1 h. The reaction mixture was charged with 328 mg of N-(3-aminopropyl)-4,4-diphenylpiperidine (1.25 mmol), and the resulting solution was heated at reflux temperature for 2 hrs. The reaction mixture was cooled, and applied to 200 g of silica packed with 5% MeOH-EtOAc. The column was eluted with 10% to 20% MeOH-EtOAc (1 L/5% change) to afford 552 mg of 2-ethyl-4-(4-nitrophenyl)-6-(methyloxy)methyl-3-(2-cyanocarboethoxy)-5-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine (77%) as a yellow foamy solid: mp 120-125° C..; Anal. Calc. for C₄₀ H₄₅ N₅ O₆.0.5H₂ O: C, 68.55; H, 6.62; N, 9.99. Found: C, 68.37; H, 6.26; N, 9.98.

f) (±)-2-Ethyl-4-(4-nitrophenyl)-6-(methyloxy)methyl-5-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine-3-carboxylic Acid: A solution of 40 mg of NaOH in 2 mL of water was added to 530 mg of 2-ethyl-4-(4-nitrophenyl)-6-(methyloxy)methyl-3-(2-cyanocarboethoxy)-5-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine (0.766 mmol) in 10 mL of dioxane. The resulting mixture was stirred at room temperature for 1 h. The solvent was removed in vacuo, the residue was partitioned between 20 mL of water (containing 200 mg of NaOH) and EtOAc (10 mL), separated, and the organic layer was extracted with 2×5 mL of water. The combined aqueous extracts were acidified (concentrated HCl, pH=3-4), and the precipitated oil was extracted with 3×10 mL of dichloromethane. The combined organic extracts were dried (Na₂ SO₄), and the solvent was removed in vacuo to afford 472 mg (97%) of 2-ethyl-4-(4-nitrophenyl)-6-(methoxy)methyl-5-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine-3-carboxylic acid as a yellow solid: mp 120-125° C.. (decomp.); Anal. Calc. for C₃₇ H₄₂ N₄ O₆.2H₂ O: C, 65.86, H, 6.87; N, 8.30. Found: C, 65.52; H, 7.05; N, 7.89.

g. (±)-5-Ethyl-4-(4-nitrophenyl)-2-(methyloxy)methyl-3-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-5-carboxamido-1,4-dihydropyridine, Hemihydrate: A mixture of 70.0 mg of 2-ethyl-4-(4-nitrophenyl)-6-(methyloxy)methyl-5-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine-3-carboxylic acid (0.110 mmol), 90.5 mg of DCC (0.435 mmol), and 16.0 mg of DMAP (0.132 mmol) in 5 mL of dry dichloromethane were stirred at room temperature for 1 hr followed by addition of 5 mL of concentrated ammonia. The resulting mixture was heated at reflux temperature for 16 hrs, cooled, filtered, dichloromethane was removed in vacuo, and the residue was dissolved in 5 mL of ethyl acetate (a small amount of dichloromethane was added to make the mixture homogeneous). The ethyl acetate solution was sequentially washed with aqueous saturated ammonium chloride solution (3×2 mL), aqueous sodium carbonate solution (2 mL), dried (Na₂ SO₄), and the solvent was removed in vacuo. The residue was chromatographed on 200 g of silica packed with NH₃ (2 M in MeOH)-MeOH-CHCl₃ (1:2:40). The column was eluted with the same solvent to give 21.0 mg of 5-ethyl-4-(4-nitrophenyl)-2-(methyloxy)methyl-3-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-5-carboxamido-1,4-dihydropyridine as a yellow solid: mp 89° C.. (decomp.); Anal. Calc. for C₃₇ H₄₃ N₅ O₅.0.5 H₂ O: C, 68.72; H, 6.86; N, 10.83. Found: C, 68.40; H, 6.91; N, 10.41

h) Ethyl 4-(2,2,2-Trifluoroethyl)oxy-3-oxobutanoate: A solution of 5.00 g of trifluoroethanol (50.0 mol.) in 5 ml of dry THF was added dropwise, over a period of 0.5 hr, to a stirred mixture of 4.00 g of 60% dispersion of NaH (100 mol.), 1.61 g of tetraburylammonium bromide (5.0 mol.), and 830 mg of NaI (5.0 mol.) in 20 ml of dry THF (water bath). The resulting mixture was stirred for 0.5 hrs, cooled to -30 ° C.., and a solution of 8.23 g of ethyl 4-chloro-3-oxobutanoate (50.0 mol.) in 10 ml of dry THF was added dropwise, over a period of 15 min, to the reaction mixture. The reaction mixture was warmed to 0° C.. over a period of 2 hrs, and stirred at room temperature for 36 hrs. The reaction mixture was quenched with 5 ml of ethanol, partitioned between 100 ml of EtOAc and 100 ml of 10% aqueous HCl solution, separated, extracted with 2×40 ml of EtOAc, the combined organic extracts were dried (Na₂ SO₄), and the solvent was removed in vacuo. The crude product was chromatographed on 400 g of silica packed with 5% EtOAc-hexane. The column was eluted with 5 to 25% EtOAc-hexane (1 L/5% change) to afford 8.75 g (77%) of Ethyl 4-(2,2,2-trifluoroethyl)oxy-3-oxobutanoate as a slightly yellow oil. The product was used in the next step after spectral characterization.

i) 2-Cyanoethyl 4-(2,2,2-Trifluoroethyl)oxy-3-oxobutanoate: A mixture of 4.04 g of ethyl 4-(2,2,2-trifluoroethyl)oxy-3-oxobutanoate (17.7 mol.) and 2.55 g of 3-hydroxypropionitrile (35.9 mol.) was heated at reflux temperature at a bath temperature of 135-150° C.. at 10 torr for 6 hrs. The reflux condenser was replaced with a distillation head and the product was distilled under reduced pressure to give 4.26 g (96%) of the desired product as a viscous oil: bp 155-158° C.. (1.5). The product was used in the next step after spectral characterization.

j) (±)-6-Methyl-4-(4-nitrophenyl)-2-((2,2,2-Trifluoroethyl)oxy)methyl-5-carboxamido-1,4-dihydrbpyridine-3-carboxylic Acid: A mixture of 1.07 g of 2-cyanoethyl 4-(2,2,2-trifluoroethyl)oxy-3-oxobutanoate (4.23 mol.) and 391 mg of ammonium acetate (5.08 mol.) in 5 ml of ethanol were heated at reflux temperature for 15 min, cooled, and 2-(p-nitrobenzilidino)acetoacetamide (4.23 mol.) was added to the reaction mixture. The resulting mixture was heated at reflux temperature for 4.5 hrs, cooled, and a solution of 406 mg of NaOH (10.2 mol.) in 5 ml of water was added to the reaction mixture. The resulting mixture was stirred at room temperature for 0.5 hr. The solvent was removed in vacuo, and the residue was partitioned between EtOAc (20 ml) and water (20 ml containing 300 mg of NaOH), separated, and the organic layer was extracted with 2×10 ml of water (each containing 150 mg of NaOH). The combined aqueous extracts were filtered, acidified to pH 2-3 with concentrated HCl, and the separated oil was extracted with 50 and then 2×20 ml of EtOAc. The combined EtOAc extracts were dried (MgSO₄), and the solvent was removed in vacuo. The crude product crystallized upon trituration with ethyl acetate to give 450 mg of 6-methyl-4-(4-nitrophenyl)-2-((2,2,2-trifluoroethyl)oxy)methyl-5-carboxamido-1,4-dihydropyridine-3-carboxylic acid (26%) as a yellow crystalline solid: mp 184° C.. (decomp.); Anal. Calc. for C₁₇ H₁₆ N₃ F₃ O₆ : C, 49.16; H, 3.88; N, 10.12. Found: 48.81; H, 3.97; N, 9.80.

k) (±)-6-Methyl-4-(4-nitrophenyl)-2-((2,2,2-trifluoroethyl)oxy)methyl-5-carboxamido-3-N-((4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine: A mixture of 102 mg of 6-methyl-4-(4-nitrophenyl)-2-((2,2,2-trifluoroethyl)oxy)methyl-5-carboxamido-1,4-dihydropyridine-3-carboxylic acid (0.230 mol.), 72.0 mg of N-3-aminopropyl-4,4-diphenylpiperidine (0.276 mol.), 119 mg of DCC (0.575 mol.), and 31.0 mg of DMAP (0.253 mol.) in 5 ml of dry dichloromethane were heated at reflux temperature for 3 hrs, cooled, filtered, and the solvent was removed in vacuo. The residue was dissolved in 5 ml of EtOAc, and sequentially washed with saturated aqueous ammonium chloride solution (2×2 ml), saturated aqueous sodium carbonate solution (2 ml), dried (Na₂ SO₄), and directly applied to 200 g of silica packed with 2N NH₃ (in methanol)-MeOH-CHCl₃ (1:2:20). The column was eluted with the same solvent system to afford 140 mg of product as a yellow solid (87%): mp 89° C.. (decomp.); Anal. Calc. for C₃₇ H₄₀ N₅ F₃ O₅ : C, 64.24; H, 5.83; N, 10.12. Found: C, 63.90; H, 5.87; N, 9.66

l) (±)-6-Ethyl-4-(4-nitrophenyl)-2-((2-azidoethyl)oxy)methyl-5-(2-cyanocarboethoxy)-3-(1,1-dimethyl)carboethoxy-1,4-dihydropyridine: A mixture of 1.00 g of t-butyl 4-(2-azidoethoxy)-3-oxopentanoate (4.10 mol.) and concentrated ammonia (0.800 g, 24.6 mol.) in 1.5 ml of t-BuOH was stirred at room temperature 17 hrs. The solvent was remove in vacuo to a give a yellow viscous oil which was used in the next step after spectral characterization. A mixture of the resulting enamide, and 0.850 g of 2-cyanoethyl 2-benzilidino-3-oxopentanoate in 15 ml of t-BuOH was heated at reflux temperature for 5 hrs. The reaction mixture was concentrated in vacuo, and the crude product was chromatographed on silica (EtOAc-hexane, 1:3) to give 836 mg of 6-ethyl-4-(4-nitrophenyl)-2-((2-azidoethyl)oxy)methyl-5-(2-cyanocarboethoxy)-3-(1,1-dimethyl)carboethoxy-1,4-dihydropyridine (56%) as a yellow viscous oil: Anal. Calc. for C₂₅ H₃₀ N6O₇ : C, 57.02; H, 5.25; N, 15.95. Found: C, 56.77; H, 5.67; N, 15.69.

m) (±)-6-Ethyl-4-(4-nitrophenyl)-2-((2-azidoethyl)oxy)methyl-3-(1,1-dimethyl)carboethoxy-1,4-dihydropyridine-5-carboxylic Acid: A solution of 91 mg of sodium hydroxide (2.3 mol.) in 7.5 ml of water was added to a solution of 800 mg of 6-ethyl-4-(4-nitrophenyl)-2-((2-azidoethyl)oxy)methyl-5-(2-cyanocarboethoxy)-3-(1,1-dimethyl)carboethoxy-1,4-dihydropyridine (1.52 mol.) in 7.5 ml of dioxane. The resulting mixture was stirred at room temperature for 3.5 hrs. The reaction mixture was washed with ether (10 ml), and the ether extract was backwashed with water (basic at pH=9-10). The combined aqueous extracts were acidified (pH=4), and the precipitated solid was collected to give the desired acid as a yellow solid (600 mg, 83%) : mp 170-173° C..; Anal. Calc. for C₂₂ H₂₇ N₅ O₇ : C, 55.80; H, 5.76; N, 14.78. Found: C, 56.07; H, 5.76; N, 14.73.

n) (±)-6-Ethyl-4-(4-nitrophenyl)-2-((2-azidoethyl)oxy)methyl-5-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-3-(1,1-dimethyl)carboethoxy-1,4-dihydropyridine: A mixture of 300 mg of 6-ethyl-4-(4-nitrophenyl)-2-((2-azidoethyl)oxy)methyl-3-(1,1-dimethyl)carboethoxy-1, 4-dihydropyridine-5-carboxylic acid (0.634 mol.), 182 mg of DMAPECD, and 93 mg of DMAP in 8 ml of dry dichloromethane were stirred at room temperature for 3 hrs. The reaction mixture was charged with 216 mg of N-(3-aminopropyl)-4,4-diphenylpiperidine (0.824 mol.), and heated at reflux temperature for 19 hrs. The reaction mixture was concentrated in vacuo and the crude product was chromatographed (5% MeOH-EtOAc) to give 400 mg of desired product (86%) as a yellow foamy solid: mp 62-67° C..; Anal. Calc. for C₄₂ H₅₁ N₇ O₆ : C, 67.26; H, 6.89; N, 13.07. Found: C, 66.96; H, 6.79; N, 12.87.

o) (±)-6-Ethyl-4-(4-nitrophenyl)-2-((2-aminoethyl)oxy)methyl-5-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-3-(1,1-dimethyl)carboethoxy-1,4-dihydropyridine: A solution of 136 mg of 6-ethyl-4-(4-nitrophenyl)-2-((2-azidoethyl)oxy)methyl-5-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-3-(1,1-dimethyl)carboethoxy-1,4-dihydropyridine (0.180 mol.), 57 mg of triphenylphosphine (0.22 mol.), and 5 ml of water in 3.5 ml of ethyl acetate were stirred at room temperature for 13 hrs. The reaction mixture was concentrated in vacuo and the crude product was chromatographed on silica (2N NH₃ (in methanol)-MeOH-CHCl₃, 1:1:9) to give 25 mg of ethyl-4-(4-nitrophenyl)-2-((2-aminoethyl)oxy)methyl-5-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-3-(1,1-dimethyl)carboethoxy-1,4-dihydropyridine as a light yellow foamy solid: mp 84-89° C..; Anal. Calc. for C₄₂ H₅₃ N₅ O₆.0.7H₂ O: C, 68.49; H, 7.44; N, 9.51. Found: C, 68.14; H, 7.00; N, 9.41.

p) (±)-2-Ethyl-4-(4-nitrophenyl)-6-((2-azidoethyl)oxy)methyl-3-(2-cyanocarboethoxy)-1,4-dihydropyridine-5-carboxylic Acid: A mixture of 2.90 g of 6-ethyl-4-(4-nitrophenyl)-2-((2-azidoethyl)oxy)methyl-5-(2-cyanocarboethoxy)-3-(1, 1-dimethyl) carboethoxy-1,4-dihydropyridine (5.51 mol.) in 10 ml of formic acid was stirred for 1.5 hrs, solvent removed in vacuo. The crude product was triturated with EtOAc and a small amount of hexane and the resulting precipitated yellow product was collected (700 mg): mp 150° C.. (decomp.). The product was used in the following steps after spectral characterization.

q) (±)-2-Ethyl-4-(4-nitrophenyl)-6-((2-azidoethyl)oxy)methyl-5-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-3-(2-cyanocarboethoxy)-1,4-dihydropyridine: A solution of 700 mg of ethyl-4-(4-nitrophenyl)-6-((2-azidoethyl)oxy)methyl-3-(2-cyanocarboethoxy)-1,4-dihydropyridine-5-carboxylic acid (1.49 mol.), 461 mg of DCC (2.23 mol.), and 145 mg of DMAP (1.19 mol.) in 10 ml of dry dichloromethane were stirred at room temperature for 1.5 hrs. The reaction mixture was charged with 570 mg of N-(3-aminopropyl)-4,4-diphenylpiperidine (1.93 mol.), and the reaction mixture was stirred for 13 hrs. The reaction mixture was filtered and applied to a flash chromatography column (silica, MeOH-EtOAc 5% to 10%) to give 815 mg of the desired product (73%) as a yellow foamy solid: mp 63-67° C..; Anal. Calc. for C₄₁ H₄₆ N₈ O₆.H₂ O: C, 64.38; H, 6.33; N, 14.65. Found: C, 64.72; H, 6.12; N, 14.62.

r) (±)-2-Ethyl-4-(4-nitrophenyl)-6-((2-azidoethyl)oxy)methyl-5-(N-(4,4-diphenylpiperidin-4-yl)propyl) carboxamido-1,4-dihydropyridine-3-carboxylic Acid: A solution of sodium hydroxide (30 mg) in 2 ml of water was added to a solution of 356 mg of 2-ethyl-4-(4-nitrophenyl)-6-((2-azidoethyl)oxy)methyl-5-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-3-(2-cyanocarboethoxy)-1,4-dihydropyridine (0.500 mol.) in 2 ml of dioxane. The resulting mixture was stirred at room temperature for 2 hrs. The solvent was removed in vacuo. The residue was dissolved in 10 ml of water and extracted with a 1:1 mixture of ether-hexane (10 ml). The aqueous extract was acidified to pH 4 (concentrated HCl), and the precipitated yellow solid was collected to give 283 mg of 2-ethyl-4-(4-nitrophenyl)-6-((2-azidoethyl)oxy)methyl-5-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine-3-carboxylic acid (82%): mp 118° C.. (decomp.); Anal. Calc for C₃₈ H₄₃ N₇ O₆ : C, 65.78; H, 6.26; N, 14.12. Found: C, 65.55; H, 6.31; N, 13.96.

s) (±)-6-Ethyl-4-(4-nitrophenyl)-2-((2-azidoethyl)oxy)methyl-5-carboxamido-3-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine: A solution of 600 mg of 2-ethyl-4-(4-nitrophenyl)-6-((2-azidoethyl)oxy)methyl-5-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine-3-carboxylic acid (0.865 mol.), DCC (357 mg, 1.73 mol.), and DMAP (85 mg, 0.692 mol.) in 15 ml of dry dichloromethane was stirred at room temperature for 2 hrs. The reaction mixture was charged with 522 mg of concentrated ammonia solution, and the reaction mixture was stirred at room temperature for 3 days. The reaction mixture was filtered, concentrated in vacuo and the crude product was chromatographed (silica, MeOH-EtOAc, 1:9, 1:8, 1:4) to give 528 mg of product as a yellow foamy solid (88%): mp 88-93° C..; Anal. Calc. for C₃₈ H₄₄ N₈ O₅.0.5H₂ O: C, 65.03; H, 6.46; N, 15.97. Found: C, 64.80; H, 5.96; N, 15.88.

t) (±)-6-Ethyl-4-(4-nitrophenyl)-2-((2-aminoethyl)oxy)methyl-5-carboxamido-3-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine: A solution of 61 mg of 6-ethyl-4-(4-nitrophenyl)-2-((2-azidoethyl)oxy)methyl-5-carboxamido-3-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine (0.088 mol.), triphenylphosphine (30 mg, 0.114 mol.), and water (2.5 mg, 0.141 mol.) in 1 ml EtOAc was stirred at room temperature for 3 days. The reaction mixture was concentrated in vacuo, and chromatographed (silica, NH₃ (2N in methanol):MeOH:CHC₃ (1:2:20)) to give 32 mg of 6-ethyl-4-(4-nitrophenyl)-2-((2-aminoethyl)oxy)methyl-5-carboxamido-3-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine (55%) as a yellow solid: mp 98-103° C..; Anal. Calc. for C₃₈ H₄₆ N₆ O₅.1.0H₂ O.0.2CH₂ Cl₂ : C, 65.38; H, 6.95; N, 11.97. Found: C, 65.39; H, 6.58; N, 11.44.

Using trimethylphosphine as the reducing agent, on a large scale (3 mol.), a 93% yield of the 6-ethyl-4-(4-nitrophenyl)-2-((2-aminoethyl)oxy) methyl-5-carboxamido-3-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine was realized. The product from this batch had the following microanalytical data: Anal. Calc. for C₃₈ H₄₆ N₆ O₅.1.3 H₂ O: C, 66.12; H, 7.10; N, 12.18. Found: C, 66.17; H, 6.69; N, 12.09

u) The enantiomers of 6-ethyl-4-(4-nitrophenyl)-2-((2-aminoethyl)oxy)methyl-5-carboxamido-3-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine were separated on a Chiracel AD (2 cm) column. The retention times on the semi-prep column were dependent on the column load. At a 60 mg load, the retention times were 128 and 228 minutes (hexane-ethanol-isopropanol (containing 3% diethylamine) 84:3:13). The retention times on the analytical Chiracel AD column (4.6 mm), using the same solvent mixture were 34 and 54 minutes (broad peaks). The plus isomer eluted first followed by the minus isomer. The purity of the final selected enantiomeric fractions were >99.9%.

(-)-6-Ethyl-4-(4-nitrophenyl)-2-((2-aminoethyl)oxy)methyl-5-carboxamido-3-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4-dihydropyridine: [a]₁₀₀ =-39.8 (+)-6-Ethyl-4-(4-nitrophenyl)-2-((2-aminoethyl)oxy)methyl-5-carboxamido-3-(N-(4,4-diphenylpiperidin-4-yl)propyl)carboxamido-1,4 dihydropyridine: [a]₁₀₀ =+40.1 ##STR5##

EXAMPLE 10 Protocol for the Determination of the Potency of α₁ Antagonists

The activity of compounds at the different human receptors was determined in vitro using cultured cell lines that selectively express the receptor of interest. These cell lines were prepared by transfecting the cloned cDNA or cloned genomic DNA or constructs containing both genomic DNA and cDNA encoding the human α-adrenergic, serotonin, histamine, and dopamine receptors as follows:

α_(1A) Human Adrenergic Receptor: The entire coding region of α1A (1719 bp) (Sequence I.D. No. 1), including 150 basepairs of 5' untranslated sequence (5' UT) and 300 bp of 3' untranslated sequence (3' UT), was cloned into the BamHI and ClaI sites of the polylinker-modified eukaryotic expression vector pCEXV-3, called EXJ.HR. The construct involved the ligation of partial overlapping human lymphocyte genomic and hippocampal cDNA clones: 5' sequence were contained on a 1.2 kb SmaI-XhoI genomic fragment (the vector-derived BamHI site was used for subcloning instead of the internal insert-derived SmaI site) and 3' sequences were contained on an 1.3 kb XhoI-ClaI cDNA fragment (the ClaI site was from the vector polylinker). Stable cell lines were obtained by cotransfection with the plasmid α1A/EXJ (expression vector containing the α1A receptor gene) and the plasmid pGCcos3neo (plasmid containing the aminoglycoside transferase gene) into LM(tk⁻), CHO, and NIH3T3 cells, using calcium phosphate technique. The cells were grown, in a controlled environment (37° C.., 5% CO₂), as monolayers in Dulbecco's modified Eagle's Medium (GIBCO, Grand Island, N.Y.) containing 25 mM glucose and supplemented with 10% bovine calf serum, 100 units/ml penicillin g, and 100 μg/ml streptomycin sulfate. Stable clones were then selected for resistance to the antibiotic G-418 (1 mg/ml), and membranes were harvested and assayed for their ability to bind [³ H]prazosin as described below (see "Radioligand Binding assays").

α_(1B) Human Adrenergic Receptor: The entire coding region 5 of α1B (1563 bp) (Sequence I.D. No. 3), including 200 basepairs and 5' untranslated sequence (5' UT) and 600 bp of 3' untranslated sequence (3' UT), was cloned into the EcoRI site of pCEXV-3 eukaryotic expression vector. The construct involved ligating the full-length containing EcoRI brainstem cDNA fragment from λ ZapII into the expression vector. Stable cell line s were selected as described above.

Human α_(1C) Adrenergic Receptor: The entire coding region of α1C (1401 bp) (Sequence I.D. No. 5), including 400 basepairs of 5' untranslated sequence (5' UT) and 200 bp of 3' untranslated sequence (3' UT), was cloned into the KpnI site of the polylinker-modified pCEXV-3-derived eukaryotic expression vector, EXJ.RH. The construct involved ligating three partiaL overlapping fragments: a 5' 0.6kb HincII genomic clone, a central 1.8 EcoRI hippocampal cDNA clone, and a 3' 0.6 Kb PstI genomic clone. The hippocampal cDNA fragment overlaps with the 5' and 3' genomic clones so that the HincII and PstI sites at the 5' and 3' ends of the cDNA clone, respectively, were utilized for ligation. This full-length clone was cloned into the KpnI site of the expression vector, using the 5' and 3' KpnI sites of the fragment, derived from vector (i.e., pBluescript) and 3'-untranslated sequences, respectively. Stable cell lines were selected as described above.

Radioligand Binding Assays: Transfected cells from culture flasks were scraped into 5 ml of 5 mM Tris-HCl, 5 mM EDTA, pH 7.5, and lysed by sonication. The cell lysates were centrifuged at 1000 rpm for 5 min at 4° C.., and the supernatant was centrifuged at 30,000×g for 20 min at 4° C.. The pellet was suspended in 50 mM Tris-HCl. 1 mM MgCl₂, and 0.1% ascorbic acid at pH 7.5. Binding of the α1 antagonist [³ H]prazosin (0.5 nM, specific activity 76.2 Ci/mmol) to membrane preparations of LM(tk⁻) cells was done in a final volume of 0.25 ml and incubated at 37° C.. for 20 min. Nonspecific binding was determined in the presence of 10 μM phentolamine. The reaction was stopped by filtration through GF/B filters using a cell harvester. Inhibition experiments, routinely consisting of 7 concentrations of the tested compounds, were analyzed using a non-linear regression curve-fitting computer program to obtain Ki values.

α₂ Human Adrenergic Receptors: To determine the potency of α₁ antagonists at the α₂ receptors, LM(tk⁻) cell lines stably transfected with the genes encoding the α_(2A), α_(2B), and α_(2C) receptors were used. The cell line expressing the α_(2A) receptor is designated L-α_(2A), and was deposited on Nov. 6, 1992 under ATCC Accession No. CRL 11180. The cell line expressing the α_(2B) receptor is designated L-NGC-α_(2B), and was deposited on Oct. 25, 1989 under ATCC Accession No. CRL10275. The cell line expressing the α_(2C) receptor is designated L-α_(2C), and was deposited on Nov. 6, 1992 under ATCC Accession No. CRL-11181. Cell lysates were prepared as described above (see Radioligand Binding Assays), and suspended in 25 mM glycylglycine buffer (pH 7.6 at room temperature). Equilibrium competition binding assay were performed using [3H]rauwolscine (0.5 nM), and nonspecific binding was determined by incubation with 10μM phentolamine. The bound radioligand was separated by filtration through GF/B filters using a cell harvester.

Human Histamine H₁ Receptor: The coding sequence of the human histamine H₁ receptor, homologous to the bovine H₁ receptor, was obtained from a human hippocampal cDNA library, and was cloned into the eukaryotic expression vector pCEXV-3. The plasmid DNA for the H₁ receptor is designated pcEXV-H1, and was deposited on Nov. 6, 1992 under ATCC Accession No. 75346. This construct was transfected into COS-7 cells by the DEAE-dextran method. Cells were harvested after 72 hours and lysed by sonication in 5 mM Tris-HCl, 5 mM EDTA, pH 7.5. The cell lysates were centrifuged at 1000 rpm for 5 min at 40° C.., and the supernatant was centrifuged at 30,000×g for 20 min. at 4° C.. The pellet was suspended in 37.8 mM NaHPO₄, 12.2 mM KH₂ PO₄, pH 7.5. The binding of the histamine H₁ antagonist [³ H]mepyramine (1 nM, specific activity: 24.8 Ci/mM) was done in a final volume of 0.25 ml and incubated at room temperature for 60 min. Nonspecific binding was determined in the presence of 10 μM mepyramine. The bound radioligand was separated by filtration through GF/B filters using a cell harvester.

Human Histamine H₂ Receptor: The coding sequence of the human H₂ receptor was obtained from a human placenta genomic library, and cloned into the cloning site of PCEXV-3 eukaryotic expression vector. The plasmid DNA for the H₂ receptor is designated pcEXV-H2, and was deposited on Nov. 6, 1992 under ATCC Accession No. 75346. This construct was transfected into COS-7 cells by the DEAE-dextran method. Cells were harvested after 72 hours and lysed by sonication in 5 mM Tris-HCl, 5 mM EDTA, pH 7.5. The cell lysates were centrifuged at 1000 rpm for 5 min at 40° C.., and the supernatant was centrifuged at 30,000×g for 20 min at 4° C.. The pellet was suspended in 37.8 mM NaHPO₄, 12.2 mM K2PO₄, pH 7.5. The binding of the histamine H₂ antagonist [³ H]tiotidine (5 nM, specific activity: 70 Ci/mM) was done in a final volume of 0.25 ml and incubated at room temperature for 60 min. Nonspecific binding was determined in the presence of 10 μM histamine. The bound radioligand was separated by filtration through GF/B filters using a cell harvester.

Human Serotonin Receptors:

5HT_(1D)α, 5HT_(1D)β, 5HT_(1E), 5HT_(1F) Receptors

The cell lysates of LM(tk-) clonal cell line stably transfected with the genes encoding each of these 5HT receptor-subtypes were prepared as described above. The cell line for the 5HT_(1D)α, receptor, designated as Ltk-8-30-84, was deposited on Apr. 17, 1990, and accorded ATCC Accession No. CRL 10421. The cell for the 5HT_(1D)β receptor, designated as Ltk-11, was deposited on Apr. 17, 1990, and accorded ATCC Accession No. CRL 10422. The cell line for the 5HT_(1E) receptor, designated 5 HT_(1E) -7, was deposited on Nov. 6, 1991, and accorded ATCC Accession No. CRL 10913. The cell line for the 5HT_(1F) receptor, designated L-5-HT_(1F), was deposited on Dec. 27, 1991, and accorded ATCC Accession No. ATCC 10957. These preparations were suspended in 50 mM Tris-HCl buffer (pH 7.4 at 37° C..) containing 10 mM MgCl₂, 0.2 mM EDTA, 10 μM pargyline, and 0.1% ascorbate. The potency of α₁ antagonists was determined in competition binding assay by incubation for 30 minutes at 37° C.. in the presence of 5 nM [3H]serotonin. Nonspecific binding was determined in the presence of 10 μM serotonin. The bound radioligand was separated by filtration through GF/B filters using a cell harvester.

Human 5HT₂ Receptor: The coding sequence of the human 5T₂ receptor was obtained from a human brain cortex cDNA library, and cloned into the cloning site of pCEXV-3 eukaryotic expression vector. This construct was transfected into LM(tk-) cells by the DEAE-dextran method. Cells were harvested after 72 hours and lysed by sonication in 5 mM Tris-HCl, 5 mM EDTA, pH 7.5. This cell line was deposited with the ATCC on Oct. 31, 1989, designated as L-NGC-5HT₂, and was accorded ATCC Accession No. CRL 10287. The cell lysates were centrifuged at 1000 rpm for 5 minutes at 4° C.., and the supernatant was centrifuged at 30,000×g for 20 minutes at 4° C.. The pellet was suspended in 50 mM Tris-HCl buffer (pH 7.7 at room temperature) containing 10 mM MgSO₄, 0.5 mM EDTA, and 0.1% ascorbate. The potency of alpha-1 antagonists at 5HT₂ receptors was determined in equilibrium competition binding assays using [3H]ketanserin (1 nM). Nonspecific binding was defined by the addition of 10 μM mianserin. The bound radioligand was separated by filtration through GF/B filters using a cell harvester.

Human Dopamine D₂ Receptors: The potency of α₁ antagonists at the D2 receptor was determined using membrane preparations from COS-7 cells transfected with the gene encoding the human D₂ receptor. The coding region for the human D2 receptor was obtained from a human striatum cDNA library, and cloned into the cloning site of PCDNA 1 eukariotic expression vector. The plasmid DNA for the D₂ receptor is designated pcEXV-D2, and was deposited on Nov. 6, 1992 under ATCC Accession No. ATC 75344. This construct was transfected into COS-7 cells by the DEAE-dextran method. Cells were harvested after 72 hours and lysed by sonication in 5 mM Tris-HCl, 5 mM EDTA, pH 7.5. The cell lysates were centrifuged at 1000 rpm for 5 minutes at 4° C.., and the supernatant was centrifuged at 30,000×g for 20 minutes at 4° C.. The pellet was suspended in 50 mM Tris-HCl (pH 7.4) containing 1 mM EDTA, 5 mM KCl, 1.5 mM CaCl₂, 4 mM MgCl₂, and 0.1% ascorbic acid. The cell lysates were incubated with [3H]spiperone (2 nM), using 10 μM (+)Butaclamol to determine nonspecific binding.

Other Dopamine receptors are prepared by known methods (D₃ : Sokoloff, P. et al., Nature, 347, 146 (1990), and deposited with the European Molecular Biological Laboratory (EMBL) Genbank as X53944; D₄ : Van Tol, H. H. M., et al., Nature, 350, 610 (1991), and deposited with EMBL Genbank as X58497; D₅ : Sunahara, R. K., et al., Nature, 350, 614 (1991), and deposited with EMBL Genbank as X58454-HU HD 5DR).

Determination of the Activity of α₁ Antagonists at Calcium Channels

The potency of α₁ antagonists at calcium channels was determined in competition binding assays of [3H]nitrendipine to membrane fragments of rat cardiac muscle, essentially as described by Glossman and Ferry (Methods in Enzymology 109:513-550, 1985). Briefly, the tissue was minced and homogenized in 50 mM Tris-HCl (pH 7.4) containing 0.1 mM phenylmethylsulfonyl fluoride. The homogenates were centrifuged at 1000 g for 15 minutes, the resulting supernatant was centrifuged at 45,000 g for 15 minutes. The 45,000 g pellet was suspended in buffer and centrifuged a second time. Aliquots of membrane protein were incubated for 30 minutes at 37° C.. in the presence of [3H]nitrendipine (1 nM), and nonspecific binding was determined in the presence of 10 μM nifedipine. The bound radioligand was separated by filtration through GF/B filters using a cell harvester.

EXAMPLE 11 Functional Properties of α₁ Antagonists in the Human Prostate

The efficacy of α₁ adrenergic antagonists for the treatment of benign prostatic hyperplasia (BPH) is related to their ability to elicit relaxation of prostate smooth muscle. An index of this efficacy can be obtained by determining the potency of α₁ antagonists to antagonize the contraction of human prostatic tissue induced by an α₁ agonist "in vitro". Furthermore, by comparing the potency of subtype selective α₁ antagonists in binding assays using human α₁ receptors with their potency to inhibit agonist-induced smooth muscle contraction, it is possible to determine which of the α₁ adrenergic receptor subtypes is involved in the contraction of prostate smooth muscle.

Methods: Prostatic adenomas were obtained at the time of surgery from patients with symptomatic BPH. These were cut into longitudinal strips of 15 mm long and 2-4 mm wide, and suspended in 5 ml organ baths containing Krebs -buffer (pH 7.4). The baths were maintained at 37° C.. and continuously oxygenated with 5% CO₂ and 95% O₂. Isometric tension was measured with a Grass Instrument FT03 force transducer interfaced with a computer. Tissue strips were contracted with varying concentrations of phenylephrine after incubating for 20 minutes in the absence and presence of at least three different concentrations of antagonist. Dose-response curves for phenylephrine were constructed, and the antagonist potency (pA₂) was estimated by the dose-ratio method. The concentration of some antagonists in the tissue bath was assessed by measuring the displacement of [3H]prazosin by aliquots of the bath medium, using membrane preparations of the cloned human α_(1C) receptor. This control was necessary to account for losses of antagonist due to adsorption to the tissue bath and/or metabolism during the time the antagonists were equilibrated with the prostate tissue.

Results:

Table 1 shows that the pA₂ values measured for a series of α₁ antagonists in human prostate tissue correlate closely (r=0.76) with the corresponding pK_(i) values measured in the α_(1C) receptor assays. In contrast, the human prostate pA₂ values correlate poorly with the pK_(i) values measured at the α_(1A) (r=-0.06) and α_(1B) (r=-0.24) adrenergic receptors. (See FIG. 2 (Panels A-C). Thus, antagonists which are more potent at blocking the α_(1C) adrenergic receptor are more effective at blocking the contraction of the human prostate than antagonists which are more potent at the α_(1A) or α_(1B) adrenergic receptors. In addition, antagonists which are selective for the α_(1C) receptor will have a better therapeutic ratio than nonselective α antagonists.

With SNAP 5036 (11), the low pA₂ observed in the prostate may be attributed to tissue absorption or metabolism.

Table 2 illustrates the cross reactivity of α₁ antagonists at other receptors such as α_(2A), α_(2B), α_(2C), histamine H₁, H₂, serotonin 5-HT_(1D)α, 5-HT_(1D)β, 5-HT_(1E), 5-HT_(1F), 5-HT₂, and dopamine D₂. Only compounds SNAP 5036, 5041, and 5089 have binding affinities which are greater than ten-fold higher at α_(1C) receptors than the binding affinities at other receptors.

Tables 3, 4 and 5 show cross reactivity of alpha-1 agonists at cloned human receptors. Table 6 shows a comparison of alpha-1 agonist cross reactivity between human neuronal receptors and human alpha-1C receptor.

                  TABLE 1                                                          ______________________________________                                         COMPARISON OF THE BINDING POTENCY (pK.sub.1) OF                                ALPHA-1 ANTAGONISTS IN CLONED HUMAN RECEPTORS                                  AND THEIR PROTENCY (pA.sub.2) TO INHIBIT                                       PROSTATE SMOOTH MUSCLE CONTRACTION                                                           Human Alpha-1                                                                  Adrenergic (pK.sub.1)                                                                      Human                                                Compound        α1A                                                                             α1B                                                                              α1C                                                                           Prostate (pA)                              ______________________________________                                         1      Prazosin     9.48   9.26  9.23 9.08                                     2      Compound 2   5.98   6.51  8.87 8.94                                     3      A-30380      7.49   7.86  8.52 8.72                                     4      5-Methyl-Urapidil                                                                           7.79   6.77  8.35 8.38                                     5      Indoramin    6.74   1.39  8.35 7.88                                     6      SKF-104858   8.48   1.50  7.60 7.68                                     7      Compound 7   6.82   7.18  8.42 7.63                                     8      Compound 8   8.52   1.07  8.48 7.46                                     9      Ccmpound 9   6.12   6.76  7.83 7.41                                     10     Terazosin    8.46   8.71  8.16 7.30                                     11     Compound 11  6.81   7.14  8.36 6.64                                     ______________________________________                                    

                                      TABLE 2                                      __________________________________________________________________________     CROSS REACTIVITY OF α.sub.1 ANTAGONISTS AT CLONED HUMAN RECEPTORS        (pK.sub.1)                                                                                                                                Cal-                                                                      Dopa-                                                                               cium                        α.sub.1 Adrenergic                                                                α.sub.2 Adrenergic                                                                Histamine                                                                            Serotonin             mine Chan-               Compound                                                                               α1A                                                                         α1B                                                                         α1C                                                                         α2a                                                                         a2b                                                                               α2c                                                                         H1 H2 5HT1Dα                                                                        5HT1Dβ                                                                         5HT1E                                                                              5HT1F                                                                              5HT2                                                                               D2   nel                 __________________________________________________________________________     Terazosin                                                                              8.46                                                                              8.71                                                                              8.16                                                                              6.26                                                                              7.51                                                                              6.64                                                                              4.00                                                                              5.04                                                                              <6.0 <6.0 <5.0                                                                               <5.0                                                                               <5.0                                                                               <5.0 5.19                Prazosin                                                                               9.48                                                                              9.26                                                                              9.23                                                                              6.76                                                                              7.64                                                                              7.65                                                                              4.00                                                                              5.19                                                                              <5.0 <5.0 ND  ND  <6.0                                                                               <5.0 4.57                5-Methylurapidil                                                                       7.79                                                                              6.77                                                                              8.35                                                                              6.63                                                                              1.38                                                                              6.88                                                                              5.16                                                                              4.47                                                                              7.30 6.82 ND  ND  <6.0                                                                               <5.0 ND                  Indoramin                                                                              6.74                                                                              7.39                                                                              8.35                                                                              4.94                                                                              5.72                                                                              5.22                                                                              7.37                                                                              5.63                                                                              <6.0 <6.0 <5.0                                                                               <5.0                                                                               <7.0                                                                               <8.0 4.53                Compound 11                                                                            6.81                                                                              7.14                                                                              8.36                                                                              6.86                                                                              6.90                                                                              6.92                                                                              5.74                                                                              7.45                                                                              <6.0 <6.0 <5.0                                                                               <5.0                                                                               <7.0                                                                               <6.0 5.18                A-30360 7.49                                                                              7.88                                                                              8.52                                                                              6.69                                                                              6.37                                                                              6.23                                                                              6.03                                                                              5.77                                                                              <6.0 <6.0 <5.0                                                                               <5.0                                                                               <8.0                                                                               <9.0 5.26                Compound 7                                                                             6.82                                                                              7.18                                                                              8.42                                                                              6.19                                                                              6.07                                                                              6.09                                                                              7.59                                                                              6.02                                                                              <6.0 <5.0 <5.0                                                                               <5.0                                                                               <8.0                                                                               <7.0 4.79                Compound 9                                                                             6.12                                                                              6.76                                                                              7.83                                                                              5.80                                                                              5.69                                                                              5.90                                                                              7.29                                                                              5.44                                                                              <6.0 <6.0 <5.0                                                                               <5.0                                                                               <7.0                                                                               <7.0 4.44                SKF-104858                                                                             8.48                                                                              7.50                                                                              7.60                                                                              7.30                                                                              8.49                                                                              7.60                                                                              5.59                                                                              5.84                                                                              <7.0 <7.0 <6.0                                                                               <7.0                                                                               <8.0                                                                               <7.0 4.68                S-Niguidipine                                                                          6.72                                                                              7.07                                                                              8.75                                                                              6.19                                                                              5.24                                                                              6.43                                                                              6.78                                                                              6.24                                                                              ND   ND   ND  ND  <7.0                                                                               <7.0 8.04                Compound 8                                                                             6.52                                                                              7.07                                                                              8.48                                                                              5.99                                                                              6.12                                                                              5.77                                                                              6.67                                                                              6.11                                                                              <6.0 <5.0 <5.0                                                                               <5.0                                                                               <7.0                                                                               <6.0 6.87                Compound 2                                                                             5.98                                                                              6.57                                                                              8.87                                                                              5.48                                                                              5.93                                                                              5.88                                                                              7.16                                                                              7.48                                                                              <7.0 <6.0 <5.0                                                                               <5.0                                                                               <6.0                                                                               <7.0 6.13                __________________________________________________________________________      ND = Not Determined                                                      

                                      TABLE 3                                      __________________________________________________________________________     CROSS REACTIVITY OF α.sub.1 ANTAGONISTS AT CLONED HUMAN RECEPTORS                Alpha-1 Adrenergic      Alpha-2 Adrenergic                             pK1     α1A                                                                              α18                                                                              α1C                                                                              α2a                                                                              a2b     Histamine                                                                              Calcium                Compound                                                                               MEAN                                                                               SEM MEAN                                                                               SEM MEAN                                                                               SEM MEAN                                                                               SEM MEAN α2c                                                                         H1  H2  Channel                __________________________________________________________________________     Terazosin                                                                              8.48    8.71    8.16    6.26    7.51 6.64                                                                              4.00                                                                               5.04    5.19               Prazosin                                                                               9.48    9.28    9.23    6.76    7.64 7.65                                                                              4.00                                                                               5.19    4.57               5-Methylurapidil                                                                       7.79    8.77    8.35    8.83    7.38 6.88                                                                              5.18                                                                               4.47    ND                 Indoramin                                                                              8.74    7.39    8.35    4.94    5.72 5.22                                                                              7.38                                                                               5.83    4.53               Compound 11                                                                            8.81    7.14    8.38    6.88    8.90 6.92                                                                              5.74                                                                               7.45    5.18               A-30360 7.49    7.88    8.52    6.69    8.31 8.23                                                                              6.03                                                                               5.77    5.28               Compound 7                                                                             8.82    7.18    8.42    8.19    8.07 8.09                                                                              7.59                                                                               8.02    4.79               Compound 9                                                                             8.12    8.78    7.83    5.80    5.69 5.90                                                                              7.29                                                                               5.44    4.44               SKF-104858                                                                             8.48    7.50    7.80    7.30    8.49 7.80                                                                              5.59                                                                               5.84    4.88               S-Niguidipine                                                                          8.12    7.07    8.75    8.19    5.24 8.43                                                                              8.78                                                                               6.24    8.04               Compound 8                                                                             6.52    7.01    8.48    5.99    6.12 5.77                                                                              8.87                                                                               6.11    6.87               Compound 2                                                                             5.98    8.57    8.87    5.48    5.93 5.88                                                                              7.18                                                                               7.48    6.13               __________________________________________________________________________     Comparison of Alpha-1 Antagonist Crossreactivity Between Human Neuronal        Receptors and Human Alpha-1c                                                   pK1                                                                            Compound   5HT1Da  5HT1Db  5HT1E  5HT1F  5HT2   D2    Ca                       __________________________________________________________________________                                                           Chann                    Terazosin  6.00    6.00    5.00   5.00   5.00   5.00  5.19                     Prazosin   5.00    5.00    ND     ND     6.00   5.00  4.57                     5-Methylurapidil                                                                          7.30    6.82    ND     ND     6.00   5.00  ND                       Indoramin  6.00    6.00    5.00   5.00   7.00   8.00  4.53                     Compound 11                                                                               6.00    6.00    5.00   5.,00  7.00   6.00  5.18                     A-30380    6.00    6.00    5.00   5.00   8.00   9.00  5.26                     Compound 7 6.00    5.00    5.00   5.00   6.00   7.00  4.79                     Compound 9 6.00    6.00    5.00   5.00   7.00   7.00  4.00                     SKF-104856 7.00    7.00    6.00   7.00   6.00   7.00  4.68                     S-Niguidipine                                                                             ND      ND      ND     ND     7.00   7.00  8.04                     Compound 8 6.00    5.00    5.00   5.00   7.00   6.00  6.87                     Compound 2 7.00    6.00    5.00   5.00   6.00   7.00  6.13                     __________________________________________________________________________      ND = Not Determined                                                            As used herein, SEM means the standard error of the mean.                

                                      TABLE 4                                      __________________________________________________________________________     CROSS REACTIVITY OF ALPHA-1 ANTAGONISTS                                        AT CLONED HUMAN RECEPTORS                                                      __________________________________________________________________________             Alpha-1 Adrenergic   Alpha-2 Adrenergic                                Ki(nM)  α1A                                                                             α1B                                                                             α1C                                                                             a2a    a2b    a2c                                 Compound                                                                               MEAN                                                                               SEM                                                                               MEAN                                                                               SEM                                                                               MEAN                                                                               SEM                                                                               MEAN                                                                               SEM                                                                               MEAN                                                                               SEM                                                                               MEAN                                __________________________________________________________________________     Terazosin                                                                              3   0.31                                                                              2   0.17                                                                              7   0.31                                                                              550 123                                                                               31  5  226                                 Prazosin                                                                               0.33                                                                               0.07                                                                              0.55                                                                               0.14                                                                              0.59                                                                               0.10                                                                              174 33 23  8  22                                  5-Methylurapidil                                                                       16  3  170 35 4   0.92                                                                              234 35 42  4  132                                 Indoramin                                                                              182 31 41  7  4   0.75                                                                              11482                                                                              3719                                                                              1905                                                                               556                                                                               4026                                Compound 11                                                                            155 20 72  23 4   1.41                                                                              134 3  126 14 120                                 A-30340 32  7  14  3  3   0.62                                                                              204 30 427 38 589                                 Compound 7                                                                             151 10 46  15 4   0.05                                                                              646 15 851 19 813                                 Compound 9                                                                             759 257                                                                               174 83 15  0.99                                                                              1585                                                                               0  2042   1259                                SKF-104856                                                                             3   0.36                                                                              32  13 25  10.35                                                                             50  38 3   2  25                                  S-Niguidipine                                                                          191 32 85  21 2   0.43                                                                              446    5754   372                                 Compound 8                                                                             302 39 85  7  3   0.29                                                                              1023                                                                               111                                                                               759 51 1698                                Compound 2                                                                             1047                                                                               106                                                                               269 65 3   0.33                                                                              3311                                                                               109                                                                               1375                                                                               103                                                                               2316                                __________________________________________________________________________                   Histamine             Calcium                                    Ki(nM)        H1         H2         Channel                                    Compound SEM  MEAN  SEM  MEAN  SEM  MEAN  SEM                                  __________________________________________________________________________     Terazosin                                                                               15   100000     9120  4222 6457                                       Prazosin 3    100000     6457  2383 26915                                      5-Methyluradipil                                                                        9    6918  1548 33884 6342                                            Indoramin                                                                               770  43    11   2344  384  29512                                      Compound 11                                                                             13   1620  41   35    0.08 6607                                       A-30340  39   933   209  1698  318  5495                                       Compound 7                                                                              19   26    6    955   22   16218                                      Compound 9    31    9    3631  680  10000                                      SKF-104856                                                                              10   2570  383  1445  127  20893                                      S-Niguidipine                                                                           63   164   11   575   86   9     1                                    Compound 8                                                                              316  214   40   776   84   135   35                                   Compound 2                                                                              341  49    6    33    4    741   17                                   __________________________________________________________________________     Ki(nM)                                                                         Compound 5HT1Da                                                                               5HT1Db                                                                               5HT1E                                                                               5HT1F                                                                               5HT2 D2  Ca Chann                               __________________________________________________________________________     Terazosin                                                                               1000  1000  10000                                                                               10000                                                                               10000                                                                               10000                                                                              6457                                   Prazosin 10000 10000 ND   ND   1000 10000                                                                              26915                                  5-Methylurapidil                                                                        50    161   ND   ND   1000 10000                                      Indoramin                                                                               1000  1000  10000                                                                               10000                                                                               100  10  29512                                  Compound 11                                                                             1000  1000  10000                                                                               10000                                                                               100  1000                                                                               6607                                   A-30360  1000  1000  10000                                                                               10000                                                                               10   1   5495                                   Compound 7                                                                              1000  10000 10000                                                                               10000                                                                               1000 100 16218                                  Compound 9                                                                              1000  1000  10000                                                                               10000                                                                               100  100 100000                                 SKF-104856                                                                              100   100   1000 100  1000 100 20893                                  S-Niguidipine                                                                           ND    ND    ND   ND   100  100 9                                      Compound 8                                                                              1000  10000 10000                                                                               10000                                                                               100  1000                                                                               135                                    Compound 2                                                                              100   1000  10000                                                                               10000                                                                               1000 100 741                                    __________________________________________________________________________      ND = Not Determined                                                      

                                      TABLE 5                                      __________________________________________________________________________     1 #STR6##                                                                      Alpha adrenergic `Ki (nM)` `Fold selectivity hAlpha1c` `n` RECEPTORS           SUMMARY                                                                              hA1a                                                                               hA1b    hA1c                                                                               rA1a   rA1b                                                                              rA1c   dA1a                                                                               dA1b    dA1c                                                                               Opioid                  __________________________________________________________________________     Ki    514.34                                                                             326.21  0.47                 3659                                                                               1467.80 22.05                       Fold  1089.6                                                                             691.0   1             1      166.0                                                                              66.6    1   0.0                     n     4   4       3                    3   3       3                           __________________________________________________________________________                                     Calcium % i.a.                                                                           Calcium % i.a.                                                                            Calcium % i.a.               hA2a                                                                               hA2b                                                                               hA2c                                                                               hH1  hH2 Ca Chl  Ag hA1a                                                                             Ant. hA1a                                                                           Ag. hA1b                                                                             Ant. hA1b                                                                           Ag.                                                                                 Ant.                 __________________________________________________________________________                                                               hA1c                 Ki 402.72                                                                             901.57                                                                             203.86                                                                             184.08                                                                              462.38                                                                             19216.16                                                                           % i.a.                                                                             0.5  11.0 2.0   14.5 0.5  99.5                 Fold                                                                              853.1                                                                              1909.9                                                                             431.9                                                                              389.9                                                                               979.5                                                                              40706.8                                                                            sem 0.4  4.2  0.0   4.6  0.4  0.4                  n  2   3   3   2    2   3   n   2    2    2     2    2    2                    __________________________________________________________________________        hD1    hD2 hD3    hD5  h5HT-A                                                                               h5HT-B                                                                             h5HT-C                                                                               h5HT-D                                                                             h5HT-E                                                                               h5HT-F                                                                             h5HT-G                 __________________________________________________________________________     Ki 8156.43                                                                               991.97                                                                             70957.78                                                                              58143.34                                                                            1083.21                                                                              2398.83             3801.89                                                                            502.82                 Fold                                                                              17278.3                                                                               2101.4                                                                             150314.2                                                                              123168.6                                                                            2294.6                                                                               5081.6                                                                             0.0   0.0 0.0   8053.8                                                                             1065.1                 n  2      2   2      2    1     1                   1   1                      __________________________________________________________________________

                                      TABLE 6                                      __________________________________________________________________________     COMPARISON OF ALPHA-1 ANTAGONIST CROSSREACTIVITY BETWEEN HUMAN                 NEURONAL RECEPTORS AND HUMAN ALPHA-1C RECEPTOR                                 (ANTAGONIST Ki NEURONAL RECEPTOR)                                              (ANTAGONIST Ki ALPHA-1C ADRENERGIC RECEPTOR)                                           Alpha-1 Adrenergic   Alpha-2 Adrenergic                                        α1A                                                                             α1B                                                                             α1C                                                                             a2a    a2b    a2c                                 Compound                                                                               MEAN                                                                               SEM                                                                               MEAN                                                                               SEM                                                                               MEAN                                                                               SEM                                                                               MEAN                                                                               SEM                                                                               MEAN                                                                               SEM                                                                               MEAN                                __________________________________________________________________________     Terazosin                                                                              1   0  0   0  1      79  16 4   1  33                                  Prazosin                                                                               1   0  1   0  1      295 55 39  14 38                                  5-Methylurapidil                                                                       4   1  38  8  1      52  8  9   1  30                                  Indoramin                                                                              41  7  9   2  1      2570                                                                               833                                                                               427 125                                                                               1349                                Compound 11                                                                            35  5  17  5  1      32  1  29  3  28                                  A-30360 11  2  5   1  1      68  10 141 12 195                                 Compound 7                                                                             40  3  17  4  1      170 4  224 5  214                                 Compound 9                                                                             51  17 12  6  1      107 0  138 0  85                                  SKF-104856                                                                             0   0  1   1  1      2   2  0   0  1                                   S-Niguidipine                                                                          107 16 40  12 1      363 0  3236                                                                               0  209                                 Compound 8                                                                             91  12 26  2  1      309 24 219 15 515                                 Compound 2                                                                             276 116                                                                               200 48 1      2455                                                                               393                                                                               871 77 699                                 __________________________________________________________________________                   Histamine             Calcium                                                  H1         H2         Channel                                    Compound SEM  MEAN  SEM  MEAN  SEM  MEAN  SEM                                  __________________________________________________________________________     Terazosin                                                                               2    14454      1318  410  933                                        Prazosin 6    169824     10965 4046 45709                                      5-Methylurapidil                                                                        2    1549  347  7586  1420                                            Indoramin                                                                               174  10    2    525   88   6607                                       Compound 11                                                                             3    417   9    8     0    1514                                       A-30360  13   309   69   562   105  1820                                       Compound 7                                                                              5    7     2    251   6    4264                                       Compound 9                                                                              0    3     1    245   46   6761                                       SKF-104856                                                                              0    102   15   58    5    832                                        S-Niguidipine                                                                           47   93    6    324   48   5     1                                    Compound 8                                                                              96   65    12   234   25   41    10                                   Compound 2                                                                              253  31    5    25    5    330   13                                   __________________________________________________________________________     ALPHA-1a SELECTIVITY                                                           Compound 5HT1Da                                                                               5HT1Db                                                                              5HT1E 5HT1F                                                                              5HT2 D2   Ca Chann                               __________________________________________________________________________     Terazosin                                                                               145   145  1445  1455                                                                               1455 1455 933                                    Prazosin 16982 16982                                                                               ND    ND  1698 16982                                                                               45709                                  5-Methylurapidil                                                                        11    34   ND    ND  224  2239                                        Indoramin                                                                               224   224  2239  2239                                                                               22   2    6607                                   Compound 11                                                                             229   299  2291  2291                                                                               23   229  1514                                   A-30360  331   331  3311  3311                                                                               3    0    1820                                   Compound 7                                                                              263   2630 2630  2630                                                                               263  26   4266                                   Compound 9                                                                              68    68   676   676 7    7    6761                                   SKF-104856                                                                              4     4    40    4   40   4    832                                    S-Niguidipine                                                                           ND    ND   ND    ND  56   56   5                                      Compound 8                                                                              302   3020 3020  3020                                                                               30   302  41                                     Compound 2                                                                              74    741  7413  7413                                                                               741  74   650                                    __________________________________________________________________________      ND = Not Determined                                                      

EXAMPLE 11

Functional Properties of α₁ Antagonists on Rat Orthostatic Hypertension

We have identified a large series of compounds (well over 150 compounds, data not shown) which exemplify the hereinabove described properties of antagonists highly selective for the α_(1C) adrenergic receptor. That is, these compounds are highly selective Alpha 1c antagonists which have less than 10 fold the affinity at cloned human Alpha 1a, Alpha 1b, Alpha 2a, Alpha 2b, Alpha 2C, Histamine H1, Dopamine D2 and Serotonin receptors. In addition, these compounds have 10 fold lower affinity at calcium channels (data not shown). We designated five of these highly selective antagonists for the α_(1C) adrenergic receptor as drugs 21-25 and used them to further characterize highly selective antagonists for the α_(1C) adrenergic receptor.

In addition, a number of these selective alpha 1c antagonists are potent at inhibiting the phenylephrine stimulated contraction of human prostate as described in Example 11. This is a well established protocol for evaluation the efficacy of drugs which may be useful for the treatment of BPH.

In addition, we have examined a number of selective alpha 1c antagonists in an in vivo canine prostate model (Felson, D., et al., J. Urol., 141, 1230-1233 (1989))which is a well characterized model for evaluating the efficacy of BPH drugs (data not shown). In this model, selective alpha 1c antagnists increase urethral pressure at doses which do not produce significant decreases in canine blood pressure. In contrast, nonselective alpha 1 antagnists do not have as large a separation between the effects on urethral pressure and the effects on blood pressure. These observations support our premise that a selective alpha 1c antagonist will have a better safety profile than a nonselective alpha 1 antagonist. We have further characterized selective alpha 1c antagonists in a rat orthostatic hypotension model. This model gives information on the vascular effects of drugs which may be indicative of their ability to produce dizziness in patients (Hieble, J. P., et al., Cardiovascular Pharmacology, 15, 845 (1990)). Our objective was to characterize the effects of selective alpha 1c antagonists on rat orthostatic hypotension and contrast the results with those obtained using nonselective alpha 1 antagonists.

Methods

Rat Orthostatic Hypotension Model

Adult male Sprague-Dawley normotensive rats were anesthetized with sodium pentobarbital (45 mg/kg, i.v.). The femoral vein and artery of the right hindllimb were cannulated for drug administration and blood pressure monitoring, respectively. Heart rate was determined by a cardiotachometer triggered by the blood pressure pulse. The rats were secured in the supine position to a board that could be tilted 90 degrees. When blood pressure and heart rate had stabilized, the rats were subjected to a 90 degree vertical (head up) tilt for 60 seconds. Changes in blood pressure and heart rate from pre-tilt levels were monitored continuously. The rats were returned to the supine position and blood pressure and heart rate were allowed to stabilize. Either an antagonist selective for the α_(1C) adrenergic receptor (designated drug 21, 22, 23, 24 or 25), an antagonist nonselective for the α_(1C) adrenergic receptor (Prazosin or Terazosin) or saline was then administered through venous cannula, either as an i.v. bolus or as an infusion, when blood pressure had stabilized, the rats were subjected to a second tilt and blood pressure and heart rate were recorded as described above. Most saline treated rats typically exhibit a greater ability to return their blood pressure toward pre-tilt levels during the second tilt. Data from the second tilt are used in statistical analysis.

Results

Table 7 shows that while nonselective alpha 1 antagonists produce significant effects on orthostatic hypotension, selective alpha 1 c antagonists do not produce significant effects. More specifically, Prazosin and Terazosin consistently cause orthostasis at the lowest dose (10 ug/kg) and, in some rats, in a dose-dependent manner. Drug 21 causes orthostasis only at the highest dose (1000 ug/kg) in 2 out of 4 rats, while the other antagonists selective for the α_(1C) adrenergic receptor causes no orthostasis at the highest dose. Placebo and 22, 23, 24, 25 did not induce orthostasis at any dose. Taken all together, this is a positive result since it is believed that orthostatic hypotension contributes to the dizziness ovserved clinically with noselective alpha 1 antagonists. This further supports our premise that a selective alpha 1c antagonist will have a better safety profile than a nonselective alpha 1 antagonist.

                                      TABLE 7                                      __________________________________________________________________________     Summary of Studies on Drug Effects on Orthostasis                                         Dose 1   Dose 2   Dose 3                                                       10 μg/kg                                                                             100 μg/kg                                                                            1000 μg/kg                                                orthostatic                                                                          BP orthostatic                                                                          BP orthostatic                                                                          BP                                          Drug     n fall in BP                                                                           fall                                                                              fall in BP                                                                           fall                                                                              fall in BP                                                                           fall                                                                              Notes                                    __________________________________________________________________________     Placebo (DMSO)                                                                          3 -     -  -     -  -     -                                           Prezosin 4 +     +  ++ or ++                                                                             ++ ++ or +++                                                                            +++                                         Terazosin                                                                               2 +     +  ++ or +++                                                                            ++ ++ or +++                                                                            +++                                         21       4 -     +  -     ++ +/-   +++                                                                               (+ in 2/4)                               22       3 -     +  -     ++ -     +++                                         23       6 -     -  -     -  -     +                                           24       6 -     -  -     +/-                                                                               -     +                                           25       4 -     -  +/-   -  -     -  (+ in 1/4)                               __________________________________________________________________________      + and - mean positive or negative findings, respectively                       +, ++ and +++ are relative to doses of the same drug but not compared to       other drugs                                                                    +/- positive findings found in some rats                                 

    __________________________________________________________________________     #             SEQUENCE LISTING                                                 - (1) GENERAL INFORMATION:                                                     -    (iii) NUMBER OF SEQUENCES: 6                                              - (2) INFORMATION FOR SEQ ID NO:1:                                             -      (i) SEQUENCE CHARACTERISTICS:                                           #pairs    (A) LENGTH: 2140 base                                                          (B) TYPE: nucleic acid                                                         (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: unknown                                                -     (ii) MOLECULE TYPE: DNA (genomic)                                        -    (iii) HYPOTHETICAL: N                                                     -     (iv) ANTI-SENSE: N                                                       -     (ix) FEATURE:                                                                      (A) NAME/KEY: CDS                                                              (B) LOCATION: 178..1893                                                        (D) OTHER INFORMATION:                                               -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:                                  - CCGGGCCAGG CACGTCCGCT CTCGGACAGC CGCTCCGCGT CACAGGAACT TG - #GGCAGGAC          60                                                                           - CCGACGGGAC CCGTGCGCGG AGCTGCATCT GGAGCCCCGC GGCTATGCCC TG - #TGCTCCCC         120                                                                           - TCCTGCCGGC CGCTCGTTCT GTGCCCCCGG CCCGGCCACC GACGGCCGCG CG - #TTGAG            177                                                                           - ATG ACT TTC CGC GAT CTC CTG AGC GTC AGT TT - #C GAG GGA CCC CGC CCG           225                                                                           Met Thr Phe Arg Asp Leu Leu Ser Val Ser Ph - #e Glu Gly Pro Arg Pro            #                 15                                                           - GAC AGC AGC GCA GGG GGC TCC AGC GCG GGC GG - #C GGC GGG GGC AGC GCG           273                                                                           Asp Ser Ser Ala Gly Gly Ser Ser Ala Gly Gl - #y Gly Gly Gly Ser Ala            #             30                                                               - GGC GGC GCG GCC CCC TCG GAG GGC CCG GCG GT - #G GGC GGC GTG CCG GGG           321                                                                           Gly Gly Ala Ala Pro Ser Glu Gly Pro Ala Va - #l Gly Gly Val Pro Gly            #         45                                                                   - GGC GCG GGC GGC GGC GGC GGC GTG GTG GGC GC - #A GGC AGC GGC GAG GAC           369                                                                           Gly Ala Gly Gly Gly Gly Gly Val Val Gly Al - #a Gly Ser Gly Glu Asp            #     60                                                                       - AAC CGG AGC TCC GCG GGG GAG CCG GGG AGC GC - #G GGC GCG GGC GGC GAC           417                                                                           Asn Arg Ser Ser Ala Gly Glu Pro Gly Ser Al - #a Gly Ala Gly Gly Asp            # 80                                                                           - GTG AAT GGC ACG GCG GCC GTC GGG GGA CTG GT - #G GTG AGC GCG CAG GGC           465                                                                           Val Asn Gly Thr Ala Ala Val Gly Gly Leu Va - #l Val Ser Ala Gln Gly            #                 95                                                           - GTG GGC GTG GGC GTC TTC CTG GCA GCC TTC AT - #C CTT ATG GCC GTG GCA           513                                                                           Val Gly Val Gly Val Phe Leu Ala Ala Phe Il - #e Leu Met Ala Val Ala            #           110                                                                - GGT AAC CTG CTT GTC ATC CTC TCA GTG GCC TG - #C AAC CGC CAC CTG CAG           561                                                                           Gly Asn Leu Leu Val Ile Leu Ser Val Ala Cy - #s Asn Arg His Leu Gln            #       125                                                                    - ACC GTC ACC AAC TAT TTC ATC GTG AAC CTG GC - #C GTG GCC GAC CTG CTG           609                                                                           Thr Val Thr Asn Tyr Phe Ile Val Asn Leu Al - #a Val Ala Asp Leu Leu            #   140                                                                        - CTG AGC GCC ACC GTA CTG CCC TTC TCG GCC AC - #C ATG GAG GTT CTG GGC           657                                                                           Leu Ser Ala Thr Val Leu Pro Phe Ser Ala Th - #r Met Glu Val Leu Gly            145                 1 - #50                 1 - #55                 1 -        #60                                                                            - TTC TGG GCC TTT GGC CGC GCC TTC TGC GAC GT - #A TGG GCC GCC GTG GAC           705                                                                           Phe Trp Ala Phe Gly Arg Ala Phe Cys Asp Va - #l Trp Ala Ala Val Asp            #               175                                                            - GTG CTG TGC TGC ACG GCC TCC ATC CTC AGC CT - #C TGC ACC ATC TCC GTG           753                                                                           Val Leu Cys Cys Thr Ala Ser Ile Leu Ser Le - #u Cys Thr Ile Ser Val            #           190                                                                - GAC CGG TAC GTG GGC GTG CGC CAC TCA CTC AA - #G TAC CCA GCC ATC ATG           801                                                                           Asp Arg Tyr Val Gly Val Arg His Ser Leu Ly - #s Tyr Pro Ala Ile Met            #       205                                                                    - ACC GAG CGC AAG GCG GCC GCC ATC CTG GCC CT - #G CTC TGG GTC GTA GCC           849                                                                           Thr Glu Arg Lys Ala Ala Ala Ile Leu Ala Le - #u Leu Trp Val Val Ala            #   220                                                                        - CTG GTG GTG TCC GTA GGG CCC CTG CTG GGC TG - #G AAG GAG CCC GTG CCC           897                                                                           Leu Val Val Ser Val Gly Pro Leu Leu Gly Tr - #p Lys Glu Pro Val Pro            225                 2 - #30                 2 - #35                 2 -        #40                                                                            - CCT GAC GAG CGC TTC TGC GGT ATC ACC GAG GA - #G GCG GGC TAC GCT GTC           945                                                                           Pro Asp Glu Arg Phe Cys Gly Ile Thr Glu Gl - #u Ala Gly Tyr Ala Val            #               255                                                            - TTC TCC TCC GTG TGC TCC TTC TAC CTG CCC AT - #G GCG GTC ATC GTG GTC           993                                                                           Phe Ser Ser Val Cys Ser Phe Tyr Leu Pro Me - #t Ala Val Ile Val Val            #           270                                                                - ATG TAC TGC CGC GTG TAC GTG GTC GCG CGC AG - #C ACC ACG CGC AGC CTC          1041                                                                           Met Tyr Cys Arg Val Tyr Val Val Ala Arg Se - #r Thr Thr Arg Ser Leu            #       285                                                                    - GAG GCA GGC GTC AAG CGC GAG CGA GGC AAG GC - #C TCC GAG GTG GTG CTG          1089                                                                           Glu Ala Gly Val Lys Arg Glu Arg Gly Lys Al - #a Ser Glu Val Val Leu            #   300                                                                        - CGC ATC CAC TGT CGC GGC GCG GCC ACG GGC GC - #C GAC GGG GCG CAC GGC          1137                                                                           Arg Ile His Cys Arg Gly Ala Ala Thr Gly Al - #a Asp Gly Ala His Gly            305                 3 - #10                 3 - #15                 3 -        #20                                                                            - ATG CGC AGC GCC AAG GGC CAC ACC TTC CGC AG - #C TCG CTC TCC GTG CGC          1185                                                                           Met Arg Ser Ala Lys Gly His Thr Phe Arg Se - #r Ser Leu Ser Val Arg            #               335                                                            - CTG CTC AAG TTC TCC CGT GAG AAG AAA GCG GC - #C AAG ACT CTG GCC ATC          1233                                                                           Leu Leu Lys Phe Ser Arg Glu Lys Lys Ala Al - #a Lys Thr Leu Ala Ile            #           350                                                                - GTC GTG GGT GTC TTC GTG CTC TGC TGG TTC CC - #T TTC TTC TTT GTC CTG          1281                                                                           Val Val Gly Val Phe Val Leu Cys Trp Phe Pr - #o Phe Phe Phe Val Leu            #       365                                                                    - CCG CTC GGC TCC TTG TTC CCG CAG CTG AAG CC - #A TCG GAG GGC GTC TTC          1329                                                                           Pro Leu Gly Ser Leu Phe Pro Gln Leu Lys Pr - #o Ser Glu Gly Val Phe            #   380                                                                        - AAG GTC ATC TTC TGG CTC GGC TAC TTC AAC AG - #C TGC GTG AAC CCG CTC          1377                                                                           Lys Val Ile Phe Trp Leu Gly Tyr Phe Asn Se - #r Cys Val Asn Pro Leu            385                 3 - #90                 3 - #95                 4 -        #00                                                                            - ATC TAC CCC TGT TCC AGC CGC GAG TTC AAG CG - #C GCC TTC CTC CGT CTC          1425                                                                           Ile Tyr Pro Cys Ser Ser Arg Glu Phe Lys Ar - #g Ala Phe Leu Arg Leu            #               415                                                            - CTG CGC TGC CAG TGC CGT CGT CGC CGG CGC CG - #C CGC CCT CTC TGG CGT          1473                                                                           Leu Arg Cys Gln Cys Arg Arg Arg Arg Arg Ar - #g Arg Pro Leu Trp Arg            #           430                                                                - GTC TAC GGC CAC CAC TGG CGG GCC TCC ACC AG - #C GGC CTG CGC CAG GAC          1521                                                                           Val Tyr Gly His His Trp Arg Ala Ser Thr Se - #r Gly Leu Arg Gln Asp            #       445                                                                    - TGC GCC CCG AGT TCG GGC GAC GCG CCC CCC GG - #A GCG CCG CTG GCC CTC          1569                                                                           Cys Ala Pro Ser Ser Gly Asp Ala Pro Pro Gl - #y Ala Pro Leu Ala Leu            #   460                                                                        - ACC GCG CTC CCC GAC CCC GAC CCC GAA CCC CC - #A GGC ACG CCC GAG ATG          1617                                                                           Thr Ala Leu Pro Asp Pro Asp Pro Glu Pro Pr - #o Gly Thr Pro Glu Met            465                 4 - #70                 4 - #75                 4 -        #80                                                                            - CAG GCT CCG GTC GCC AGC CGT CGA AAG CCA CC - #C AGC GCC TTC CGC GAG          1665                                                                           Gln Ala Pro Val Ala Ser Arg Arg Lys Pro Pr - #o Ser Ala Phe Arg Glu            #               495                                                            - TGG AGG CTG CTG GGG CCG TTC CGG AGA CCC AC - #G ACC CAG CTG CGC GCC          1713                                                                           Trp Arg Leu Leu Gly Pro Phe Arg Arg Pro Th - #r Thr Gln Leu Arg Ala            #           510                                                                - AAA GTC TCC AGC CTG TCG CAC AAG ATC CGC GC - #C GGG GGC GCG CAG CGC          1761                                                                           Lys Val Ser Ser Leu Ser His Lys Ile Arg Al - #a Gly Gly Ala Gln Arg            #       525                                                                    - GCA GAG GCA GCG TGC GCC CAG CGC TCA GAG GT - #G GAG GCT GTG TCC CTA          1809                                                                           Ala Glu Ala Ala Cys Ala Gln Arg Ser Glu Va - #l Glu Ala Val Ser Leu            #   540                                                                        - GGC GTC CCA CAC GAG GTG GCC GAG GGC GCC AC - #C TGC CAG GCC TAC GAA          1857                                                                           Gly Val Pro His Glu Val Ala Glu Gly Ala Th - #r Cys Gln Ala Tyr Glu            545                 5 - #50                 5 - #55                 5 -        #60                                                                            - TTG GCC GAC TAC AGC AAC CTA CGG GAG ACC GA - #T ATT TAAGGACCCC               1903                                                                           Leu Ala Asp Tyr Ser Asn Leu Arg Glu Thr As - #p Ile                            #               570                                                            - AGAGCTAGGC CGCGGAGTGT GCTGGGCTTG GGGGTAAGGG GGACCAGAGA GG - #CGGGCTGG        1963                                                                           - TGTTCTAAGA GCCCCCGTGC AAATCGGAGA CCCGGAAACT GATCAGGGCA GC - #TGCTCTGT        2023                                                                           - GACATCCCTG AGGAACTGGG CAGAGCTTGA GGCTGGAGCC CTTGAAAGGT GA - #AAAGTAGT        2083                                                                           - GGGGCCCCCT GCTGGACTCA GGTGCCCAGA ACTCTTTTCT TAGAAGGGAG AG - #GCTGC           2140                                                                           - (2) INFORMATION FOR SEQ ID NO:2:                                             -      (i) SEQUENCE CHARACTERISTICS:                                           #acids    (A) LENGTH: 572 amino                                                          (B) TYPE: amino acid                                                           (D) TOPOLOGY: linear                                                 -     (ii) MOLECULE TYPE: protein                                              -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:                                  - Met Thr Phe Arg Asp Leu Leu Ser Val Ser Ph - #e Glu Gly Pro Arg Pro          #                 15                                                           - Asp Ser Ser Ala Gly Gly Ser Ser Ala Gly Gl - #y Gly Gly Gly Ser Ala          #             30                                                               - Gly Gly Ala Ala Pro Ser Glu Gly Pro Ala Va - #l Gly Gly Val Pro Gly          #         45                                                                   - Gly Ala Gly Gly Gly Gly Gly Val Val Gly Al - #a Gly Ser Gly Glu Asp          #     60                                                                       - Asn Arg Ser Ser Ala Gly Glu Pro Gly Ser Al - #a Gly Ala Gly Gly Asp          # 80                                                                           - Val Asn Gly Thr Ala Ala Val Gly Gly Leu Va - #l Val Ser Ala Gln Gly          #                 95                                                           - Val Gly Val Gly Val Phe Leu Ala Ala Phe Il - #e Leu Met Ala Val Ala          #           110                                                                - Gly Asn Leu Leu Val Ile Leu Ser Val Ala Cy - #s Asn Arg His Leu Gln          #       125                                                                    - Thr Val Thr Asn Tyr Phe Ile Val Asn Leu Al - #a Val Ala Asp Leu Leu          #   140                                                                        - Leu Ser Ala Thr Val Leu Pro Phe Ser Ala Th - #r Met Glu Val Leu Gly          145                 1 - #50                 1 - #55                 1 -        #60                                                                            - Phe Trp Ala Phe Gly Arg Ala Phe Cys Asp Va - #l Trp Ala Ala Val Asp          #               175                                                            - Val Leu Cys Cys Thr Ala Ser Ile Leu Ser Le - #u Cys Thr Ile Ser Val          #           190                                                                - Asp Arg Tyr Val Gly Val Arg His Ser Leu Ly - #s Tyr Pro Ala Ile Met          #       205                                                                    - Thr Glu Arg Lys Ala Ala Ala Ile Leu Ala Le - #u Leu Trp Val Val Ala          #   220                                                                        - Leu Val Val Ser Val Gly Pro Leu Leu Gly Tr - #p Lys Glu Pro Val Pro          225                 2 - #30                 2 - #35                 2 -        #40                                                                            - Pro Asp Glu Arg Phe Cys Gly Ile Thr Glu Gl - #u Ala Gly Tyr Ala Val          #               255                                                            - Phe Ser Ser Val Cys Ser Phe Tyr Leu Pro Me - #t Ala Val Ile Val Val          #           270                                                                - Met Tyr Cys Arg Val Tyr Val Val Ala Arg Se - #r Thr Thr Arg Ser Leu          #       285                                                                    - Glu Ala Gly Val Lys Arg Glu Arg Gly Lys Al - #a Ser Glu Val Val Leu          #   300                                                                        - Arg Ile His Cys Arg Gly Ala Ala Thr Gly Al - #a Asp Gly Ala His Gly          305                 3 - #10                 3 - #15                 3 -        #20                                                                            - Met Arg Ser Ala Lys Gly His Thr Phe Arg Se - #r Ser Leu Ser Val Arg          #               335                                                            - Leu Leu Lys Phe Ser Arg Glu Lys Lys Ala Al - #a Lys Thr Leu Ala Ile          #           350                                                                - Val Val Gly Val Phe Val Leu Cys Trp Phe Pr - #o Phe Phe Phe Val Leu          #       365                                                                    - Pro Leu Gly Ser Leu Phe Pro Gln Leu Lys Pr - #o Ser Glu Gly Val Phe          #   380                                                                        - Lys Val Ile Phe Trp Leu Gly Tyr Phe Asn Se - #r Cys Val Asn Pro Leu          385                 3 - #90                 3 - #95                 4 -        #00                                                                            - Ile Tyr Pro Cys Ser Ser Arg Glu Phe Lys Ar - #g Ala Phe Leu Arg Leu          #               415                                                            - Leu Arg Cys Gln Cys Arg Arg Arg Arg Arg Ar - #g Arg Pro Leu Trp Arg          #           430                                                                - Val Tyr Gly His His Trp Arg Ala Ser Thr Se - #r Gly Leu Arg Gln Asp          #       445                                                                    - Cys Ala Pro Ser Ser Gly Asp Ala Pro Pro Gl - #y Ala Pro Leu Ala Leu          #   460                                                                        - Thr Ala Leu Pro Asp Pro Asp Pro Glu Pro Pr - #o Gly Thr Pro Glu Met          465                 4 - #70                 4 - #75                 4 -        #80                                                                            - Gln Ala Pro Val Ala Ser Arg Arg Lys Pro Pr - #o Ser Ala Phe Arg Glu          #               495                                                            - Trp Arg Leu Leu Gly Pro Phe Arg Arg Pro Th - #r Thr Gln Leu Arg Ala          #           510                                                                - Lys Val Ser Ser Leu Ser His Lys Ile Arg Al - #a Gly Gly Ala Gln Arg          #       525                                                                    - Ala Glu Ala Ala Cys Ala Gln Arg Ser Glu Va - #l Glu Ala Val Ser Leu          #   540                                                                        - Gly Val Pro His Glu Val Ala Glu Gly Ala Th - #r Cys Gln Ala Tyr Glu          545                 5 - #50                 5 - #55                 5 -        #60                                                                            - Leu Ala Asp Tyr Ser Asn Leu Arg Glu Thr As - #p Ile                          #               570                                                            - (2) INFORMATION FOR SEQ ID NO:3:                                             -      (i) SEQUENCE CHARACTERISTICS:                                           #pairs    (A) LENGTH: 1738 base                                                          (B) TYPE: nucleic acid                                                         (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: unknown                                                -     (ii) MOLECULE TYPE: DNA (genomic)                                        -    (iii) HYPOTHETICAL: N                                                     -     (iv) ANTI-SENSE: N                                                       -     (ix) FEATURE:                                                                      (A) NAME/KEY: CDS                                                              (B) LOCATION: 124..1683                                                        (D) OTHER INFORMATION:                                               -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:                                  - GCCAGGAGGG CGCCTCTGGG AAGAAGACCA CGGGGGAAGC AAAGTTTCAG GG - #CAGCTGAG          60                                                                           - GAGCCTTCGC CGCAGCCCTT CCGAGCCCAA TCATCCCCCA GGCTATGGAG GG - #CGGACTCT         120                                                                           - AAG ATG AAT CCC GAC CTG GAC ACC GGC CAC AA - #C ACA TCA GCA CCT GCC           168                                                                           #His Asn Thr Ser Ala Pro AlaThr Gly                                            #   15                                                                         - CAC TGG GGA GAG TTG AAA AAT GCC AAC TTC AC - #T GGC CCC AAC CAG ACC           216                                                                           His Trp Gly Glu Leu Lys Asn Ala Asn Phe Th - #r Gly Pro Asn Gln Thr            #                 30                                                           - TCG AGC AAC TCC ACA CTG CCC CAG CTG GAC AT - #C ACC AGG GCC ATC TCT           264                                                                           Ser Ser Asn Ser Thr Leu Pro Gln Leu Asp Il - #e Thr Arg Ala Ile Ser            #             45                                                               - GTG GGC CTG GTG CTG GGC GCC TTC ATC CTC TT - #T GCC ATC GTG GGC AAC           312                                                                           Val Gly Leu Val Leu Gly Ala Phe Ile Leu Ph - #e Ala Ile Val Gly Asn            #         60                                                                   - ATC CTA GTC ATC TTG TCT GTG GCC TGC AAC CG - #G CAC CTG CGG ACG CCC           360                                                                           Ile Leu Val Ile Leu Ser Val Ala Cys Asn Ar - #g His Leu Arg Thr Pro            #     75                                                                       - ACC AAC TAC TTC ATT GTC AAC CTG GCC ATG GC - #C GAC CTG CTG TTG AGC           408                                                                           Thr Asn Tyr Phe Ile Val Asn Leu Ala Met Al - #a Asp Leu Leu Leu Ser            # 95                                                                           - TTC ACC GTC CTG CCC TTC TCA GCG GCC CTA GA - #G GTG CTC GGC TAC TGG           456                                                                           Phe Thr Val Leu Pro Phe Ser Ala Ala Leu Gl - #u Val Leu Gly Tyr Trp            #               110                                                            - GTG CTG GGG CGG ATC TTC TGT GAC ATC TGG GC - #A GCC GTG GAT GTC CTG           504                                                                           Val Leu Gly Arg Ile Phe Cys Asp Ile Trp Al - #a Ala Val Asp Val Leu            #           125                                                                - TGC TGC ACA GCG TCC ATT CTG AGC CTG TGC GC - #C ATC TCC ATC GAT CGC           552                                                                           Cys Cys Thr Ala Ser Ile Leu Ser Leu Cys Al - #a Ile Ser Ile Asp Arg            #       140                                                                    - TAC ATC GGG GTG CGC TAC TCT CTG CAG TAT CC - #C ACG CTG GTC ACC CGG           600                                                                           Tyr Ile Gly Val Arg Tyr Ser Leu Gln Tyr Pr - #o Thr Leu Val Thr Arg            #   155                                                                        - AGG AAG GCC ATC TTG GCG CTG CTC AGT GTC TG - #G GTC TTG TCC ACC GTC           648                                                                           Arg Lys Ala Ile Leu Ala Leu Leu Ser Val Tr - #p Val Leu Ser Thr Val            160                 1 - #65                 1 - #70                 1 -        #75                                                                            - ATC TCC ATC GGG CCT CTC CTT GGG TGG AAG GA - #G CCG GCA CCC AAC GAT           696                                                                           Ile Ser Ile Gly Pro Leu Leu Gly Trp Lys Gl - #u Pro Ala Pro Asn Asp            #               190                                                            - GAC AAG GAG TGC GGG GTC ACC GAA GAA CCC TT - #C TAT GCC CTC TTC TCC           744                                                                           Asp Lys Glu Cys Gly Val Thr Glu Glu Pro Ph - #e Tyr Ala Leu Phe Ser            #           205                                                                - TCT CTG GGC TCC TTC TAC ATC CCT CTG GCG GT - #C ATT CTA GTC ATG TAC           792                                                                           Ser Leu Gly Ser Phe Tyr Ile Pro Leu Ala Va - #l Ile Leu Val Met Tyr            #       220                                                                    - TGC CGT GTC TAT ATA GTG GCC AAG AGA ACC AC - #C AAG AAC CTA GAG GCA           840                                                                           Cys Arg Val Tyr Ile Val Ala Lys Arg Thr Th - #r Lys Asn Leu Glu Ala            #   235                                                                        - GGA GTC ATG AAG GAG ATG TCC AAC TCC AAG GA - #G CTG ACC CTG AGG ATC           888                                                                           Gly Val Met Lys Glu Met Ser Asn Ser Lys Gl - #u Leu Thr Leu Arg Ile            240                 2 - #45                 2 - #50                 2 -        #55                                                                            - CAT TCC AAG AAC TTT CAC GAG GAC ACC CTT AG - #C AGT ACC AAG GCC AAG           936                                                                           His Ser Lys Asn Phe His Glu Asp Thr Leu Se - #r Ser Thr Lys Ala Lys            #               270                                                            - GGC CAC AAC CCC AGG AGT TCC ATA GCT GTC AA - #A CTT TTT AAG TTC TCC           984                                                                           Gly His Asn Pro Arg Ser Ser Ile Ala Val Ly - #s Leu Phe Lys Phe Ser            #           285                                                                - AGG GAA AAG AAA GCA GCT AAG ACG TTG GGC AT - #T GTG GTC GGT ATG TTC          1032                                                                           Arg Glu Lys Lys Ala Ala Lys Thr Leu Gly Il - #e Val Val Gly Met Phe            #       300                                                                    - ATC TTG TGC TGG CTA CCC TTC TTC ATC GCT CT - #A CCG CTT GGC TCC TTG          1080                                                                           Ile Leu Cys Trp Leu Pro Phe Phe Ile Ala Le - #u Pro Leu Gly Ser Leu            #   315                                                                        - TTC TCC ACC CTG AAG CCC CCC GAC GCC GTG TT - #C AAG GTG GTG TTC TGG          1128                                                                           Phe Ser Thr Leu Lys Pro Pro Asp Ala Val Ph - #e Lys Val Val Phe Trp            320                 3 - #25                 3 - #30                 3 -        #35                                                                            - CTG GGC TAC TTC AAC AGC TGC CTC AAC CCC AT - #C ATC TAC CCA TGC TCC          1176                                                                           Leu Gly Tyr Phe Asn Ser Cys Leu Asn Pro Il - #e Ile Tyr Pro Cys Ser            #               350                                                            - AGC AAG GAG TTC AAG CGC GCT TTC GTG CGC AT - #C CTC GGG TGC CAG TGC          1224                                                                           Ser Lys Glu Phe Lys Arg Ala Phe Val Arg Il - #e Leu Gly Cys Gln Cys            #           365                                                                - CGC GGC CGC GGC CGC CGC CGA CGC CGC CGC CG - #C CGT CGC CTG GGC GGC          1272                                                                           Arg Gly Arg Gly Arg Arg Arg Arg Arg Arg Ar - #g Arg Arg Leu Gly Gly            #       380                                                                    - TGC GCC TAC ACC TAC CGG CCG TGG ACG CGC GG - #C GGC TCG CTG GAG CGC          1320                                                                           Cys Ala Tyr Thr Tyr Arg Pro Trp Thr Arg Gl - #y Gly Ser Leu Glu Arg            #   395                                                                        - TCG CAG TCG CGC AAG GAC TCG CTG GAC GAC AG - #C GGC AGC TGC CTG AGC          1368                                                                           Ser Gln Ser Arg Lys Asp Ser Leu Asp Asp Se - #r Gly Ser Cys Leu Ser            400                 4 - #05                 4 - #10                 4 -        #15                                                                            - GGC AGC CAG CGG ACC CTG CCC TCG GCC TCG CC - #G AGC CCG GGC TAC CTG          1416                                                                           Gly Ser Gln Arg Thr Leu Pro Ser Ala Ser Pr - #o Ser Pro Gly Tyr Leu            #               430                                                            - GGC CGC GGC GCG CCA CCG CCA GTC GAG CTG TG - #C GCC TTC CCC GAG TGG          1464                                                                           Gly Arg Gly Ala Pro Pro Pro Val Glu Leu Cy - #s Ala Phe Pro Glu Trp            #           445                                                                - AAG GCG CCC GGC GCC CTC CTG AGC CTG CCC GC - #G CCT GAG CCC CCC GGC          1512                                                                           Lys Ala Pro Gly Ala Leu Leu Ser Leu Pro Al - #a Pro Glu Pro Pro Gly            #       460                                                                    - CGC CGC GGC CGC CAC GAC TCG GGC CCG CTC TT - #C ACC TTC AAG CTC CTG          1560                                                                           Arg Arg Gly Arg His Asp Ser Gly Pro Leu Ph - #e Thr Phe Lys Leu Leu            #   475                                                                        - ACC GAG CCC GAG AGC CCC GGG ACC GAC GGC GG - #C GCC AGC AAC GGA GGC          1608                                                                           Thr Glu Pro Glu Ser Pro Gly Thr Asp Gly Gl - #y Ala Ser Asn Gly Gly            480                 4 - #85                 4 - #90                 4 -        #95                                                                            - TGC GAG GCC GCG GCC GAC GTG GCC AAC GGG CA - #G CCG GGC TTC AAA AGC          1656                                                                           Cys Glu Ala Ala Ala Asp Val Ala Asn Gly Gl - #n Pro Gly Phe Lys Ser            #               510                                                            - AAC ATG CCC CTG GCG CCC GGG CAG TTT TAGGGCCCC - #C GTGCGCAGCT                1703                                                                           Asn Met Pro Leu Ala Pro Gly Gln Phe                                            #           520                                                                #     1738         GAAA ACATCGTGGG GGGGA                                       - (2) INFORMATION FOR SEQ ID NO:4:                                             -      (i) SEQUENCE CHARACTERISTICS:                                           #acids    (A) LENGTH: 520 amino                                                          (B) TYPE: amino acid                                                           (D) TOPOLOGY: linear                                                 -     (ii) MOLECULE TYPE: protein                                              -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:4:                                  - Met Asn Pro Asp Leu Asp Thr Gly His Asn Th - #r Ser Ala Pro Ala His          #                 15                                                           - Trp Gly Glu Leu Lys Asn Ala Asn Phe Thr Gl - #y Pro Asn Gln Thr Ser          #             30                                                               - Ser Asn Ser Thr Leu Pro Gln Leu Asp Ile Th - #r Arg Ala Ile Ser Val          #         45                                                                   - Gly Leu Val Leu Gly Ala Phe Ile Leu Phe Al - #a Ile Val Gly Asn Ile          #     60                                                                       - Leu Val Ile Leu Ser Val Ala Cys Asn Arg Hi - #s Leu Arg Thr Pro Thr          # 80                                                                           - Asn Tyr Phe Ile Val Asn Leu Ala Met Ala As - #p Leu Leu Leu Ser Phe          #                 95                                                           - Thr Val Leu Pro Phe Ser Ala Ala Leu Glu Va - #l Leu Gly Tyr Trp Val          #           110                                                                - Leu Gly Arg Ile Phe Cys Asp Ile Trp Ala Al - #a Val Asp Val Leu Cys          #       125                                                                    - Cys Thr Ala Ser Ile Leu Ser Leu Cys Ala Il - #e Ser Ile Asp Arg Tyr          #   140                                                                        - Ile Gly Val Arg Tyr Ser Leu Gln Tyr Pro Th - #r Leu Val Thr Arg Arg          145                 1 - #50                 1 - #55                 1 -        #60                                                                            - Lys Ala Ile Leu Ala Leu Leu Ser Val Trp Va - #l Leu Ser Thr Val Ile          #               175                                                            - Ser Ile Gly Pro Leu Leu Gly Trp Lys Glu Pr - #o Ala Pro Asn Asp Asp          #           190                                                                - Lys Glu Cys Gly Val Thr Glu Glu Pro Phe Ty - #r Ala Leu Phe Ser Ser          #       205                                                                    - Leu Gly Ser Phe Tyr Ile Pro Leu Ala Val Il - #e Leu Val Met Tyr Cys          #   220                                                                        - Arg Val Tyr Ile Val Ala Lys Arg Thr Thr Ly - #s Asn Leu Glu Ala Gly          225                 2 - #30                 2 - #35                 2 -        #40                                                                            - Val Met Lys Glu Met Ser Asn Ser Lys Glu Le - #u Thr Leu Arg Ile His          #               255                                                            - Ser Lys Asn Phe His Glu Asp Thr Leu Ser Se - #r Thr Lys Ala Lys Gly          #           270                                                                - His Asn Pro Arg Ser Ser Ile Ala Val Lys Le - #u Phe Lys Phe Ser Arg          #       285                                                                    - Glu Lys Lys Ala Ala Lys Thr Leu Gly Ile Va - #l Val Gly Met Phe Ile          #   300                                                                        - Leu Cys Trp Leu Pro Phe Phe Ile Ala Leu Pr - #o Leu Gly Ser Leu Phe          305                 3 - #10                 3 - #15                 3 -        #20                                                                            - Ser Thr Leu Lys Pro Pro Asp Ala Val Phe Ly - #s Val Val Phe Trp Leu          #               335                                                            - Gly Tyr Phe Asn Ser Cys Leu Asn Pro Ile Il - #e Tyr Pro Cys Ser Ser          #           350                                                                - Lys Glu Phe Lys Arg Ala Phe Val Arg Ile Le - #u Gly Cys Gln Cys Arg          #       365                                                                    - Gly Arg Gly Arg Arg Arg Arg Arg Arg Arg Ar - #g Arg Leu Gly Gly Cys          #   380                                                                        - Ala Tyr Thr Tyr Arg Pro Trp Thr Arg Gly Gl - #y Ser Leu Glu Arg Ser          385                 3 - #90                 3 - #95                 4 -        #00                                                                            - Gln Ser Arg Lys Asp Ser Leu Asp Asp Ser Gl - #y Ser Cys Leu Ser Gly          #               415                                                            - Ser Gln Arg Thr Leu Pro Ser Ala Ser Pro Se - #r Pro Gly Tyr Leu Gly          #           430                                                                - Arg Gly Ala Pro Pro Pro Val Glu Leu Cys Al - #a Phe Pro Glu Trp Lys          #       445                                                                    - Ala Pro Gly Ala Leu Leu Ser Leu Pro Ala Pr - #o Glu Pro Pro Gly Arg          #   460                                                                        - Arg Gly Arg His Asp Ser Gly Pro Leu Phe Th - #r Phe Lys Leu Leu Thr          465                 4 - #70                 4 - #75                 4 -        #80                                                                            - Glu Pro Glu Ser Pro Gly Thr Asp Gly Gly Al - #a Ser Asn Gly Gly Cys          #               495                                                            - Glu Ala Ala Ala Asp Val Ala Asn Gly Gln Pr - #o Gly Phe Lys Ser Asn          #           510                                                                - Met Pro Leu Ala Pro Gly Gln Phe                                              #       520                                                                    - (2) INFORMATION FOR SEQ ID NO:5:                                             -      (i) SEQUENCE CHARACTERISTICS:                                           #pairs    (A) LENGTH: 1639 base                                                          (B) TYPE: nucleic acid                                                         (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: unknown                                                -     (ii) MOLECULE TYPE: DNA (genomic)                                        -    (iii) HYPOTHETICAL: N                                                     -     (iv) ANTI-SENSE: N                                                       -     (ix) FEATURE:                                                                      (A) NAME/KEY: CDS                                                              (B) LOCATION: 126..1523                                                        (D) OTHER INFORMATION:                                               -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:5:                                  - CCAGCCAAAC CACTGGCAGG CTCCCTCCAG CCGAGACCTT TTATTCCCGG CT - #CCCGAGCT          60                                                                           - CCGCCTCCGC GCCAGCCCGG GAGGTGGCCC TGACAGCCGG ACCTCGCCCG GC - #CCCGGCTG         120                                                                           #GAC AGC TCC AAC TGC        167 AAT GCT TCC                                    #Ala Ser Asp Ser Ser Asn Cysy Asn                                              #     10                                                                       - ACC CAA CCG CCG GCA CCG GTG AAC ATT TCC AA - #G GCC ATT CTG CTC GGG           215                                                                           Thr Gln Pro Pro Ala Pro Val Asn Ile Ser Ly - #s Ala Ile Leu Leu Gly            # 30                                                                           - GTG ATC TTG GGG GGC CTC ATT CTT TTC GGG GT - #G CTG GGT AAC ATC CTA           263                                                                           Val Ile Leu Gly Gly Leu Ile Leu Phe Gly Va - #l Leu Gly Asn Ile Leu            #                 45                                                           - GTG ATC CTC TCC GTA GCC TGT CAC CGA CAC CT - #G CAC TCA GTC ACG CAC           311                                                                           Val Ile Leu Ser Val Ala Cys His Arg His Le - #u His Ser Val Thr His            #             60                                                               - TAC TAC ATC GTC AAC CTG GCG GTG GCC GAC CT - #C CTG CTC ACC TCC ACG           359                                                                           Tyr Tyr Ile Val Asn Leu Ala Val Ala Asp Le - #u Leu Leu Thr Ser Thr            #         75                                                                   - GTG CTG CCC TTC TCC GCC ATC TTC GAG GTC CT - #A GGC TAC TGG GCC TTC           407                                                                           Val Leu Pro Phe Ser Ala Ile Phe Glu Val Le - #u Gly Tyr Trp Ala Phe            #     90                                                                       - GGC AGG GTC TTC TGC AAC ATC TGG GCG GCA GT - #G GAT GTG CTG TGC TGC           455                                                                           Gly Arg Val Phe Cys Asn Ile Trp Ala Ala Va - #l Asp Val Leu Cys Cys            #110                                                                           - ACC GCG TCC ATC ATG GGC CTC TGC ATC ATC TC - #C ATC GAC CGC TAC ATC           503                                                                           Thr Ala Ser Ile Met Gly Leu Cys Ile Ile Se - #r Ile Asp Arg Tyr Ile            #               125                                                            - GGC GTG AGC TAC CCG CTG CGC TAC CCA ACC AT - #C GTC ACC CAG AGG AGG           551                                                                           Gly Val Ser Tyr Pro Leu Arg Tyr Pro Thr Il - #e Val Thr Gln Arg Arg            #           140                                                                - GGT CTC ATG GCT CTG CTC TGC GTC TGG GCA CT - #C TCC CTG GTC ATA TCC           599                                                                           Gly Leu Met Ala Leu Leu Cys Val Trp Ala Le - #u Ser Leu Val Ile Ser            #       155                                                                    - ATT GGA CCC CTG TTC GGC TGG AGG CAG CCG GC - #C CCC GAG GAC GAG ACC           647                                                                           Ile Gly Pro Leu Phe Gly Trp Arg Gln Pro Al - #a Pro Glu Asp Glu Thr            #   170                                                                        - ATC TGC CAG ATC AAC GAG GAG CCG GGC TAC GT - #G CTC TTC TCA GCG CTG           695                                                                           Ile Cys Gln Ile Asn Glu Glu Pro Gly Tyr Va - #l Leu Phe Ser Ala Leu            175                 1 - #80                 1 - #85                 1 -        #90                                                                            - GGC TCC TTC TAC CTG CCT CTG GCC ATC ATC CT - #G GTC ATG TAC TGC CGC           743                                                                           Gly Ser Phe Tyr Leu Pro Leu Ala Ile Ile Le - #u Val Met Tyr Cys Arg            #               205                                                            - GTC TAC GTG GTG GCC AAG AGG GAG AGC CGG GG - #C CTC AAG TCT GGC CTC           791                                                                           Val Tyr Val Val Ala Lys Arg Glu Ser Arg Gl - #y Leu Lys Ser Gly Leu            #           220                                                                - AAG ACC GAC AAG TCG GAC TCG GAG CAA GTG AC - #G CTC CGC ATC CAT CGG           839                                                                           Lys Thr Asp Lys Ser Asp Ser Glu Gln Val Th - #r Leu Arg Ile His Arg            #       235                                                                    - AAA AAC GCC CCG GCA GGA GGC AGC GGG ATG GC - #C AGC GCC AAG ACC AAG           887                                                                           Lys Asn Ala Pro Ala Gly Gly Ser Gly Met Al - #a Ser Ala Lys Thr Lys            #   250                                                                        - ACG CAC TTC TCA GTG AGG CTC CTC AAG TTC TC - #C CGG GAG AAG AAA GCG           935                                                                           Thr His Phe Ser Val Arg Leu Leu Lys Phe Se - #r Arg Glu Lys Lys Ala            255                 2 - #60                 2 - #65                 2 -        #70                                                                            - GCC AAA ACG CTG GGC ATC GTG GTC GGC TGC TT - #C GTC CTC TGC TGG CTG           983                                                                           Ala Lys Thr Leu Gly Ile Val Val Gly Cys Ph - #e Val Leu Cys Trp Leu            #               285                                                            - CCT TTT TTC TTA GTC ATG CCC ATT GGG TCT TT - #C TTC CCT GAT TTC AAG          1031                                                                           Pro Phe Phe Leu Val Met Pro Ile Gly Ser Ph - #e Phe Pro Asp Phe Lys            #           300                                                                - CCC TCT GAA ACA GTT TTT AAA ATA GTA TTT TG - #G CTC GGA TAT CTA AAC          1079                                                                           Pro Ser Glu Thr Val Phe Lys Ile Val Phe Tr - #p Leu Gly Tyr Leu Asn            #       315                                                                    - AGC TGC ATC AAC CCC ATC ATA TAC CCA TGC TC - #C AGC CAA GAG TTC AAA          1127                                                                           Ser Cys Ile Asn Pro Ile Ile Tyr Pro Cys Se - #r Ser Gln Glu Phe Lys            #   330                                                                        - AAG GCC TTT CAG AAT GTC TTG AGA ATC CAG TG - #T CTC TGC AGA AAG CAG          1175                                                                           Lys Ala Phe Gln Asn Val Leu Arg Ile Gln Cy - #s Leu Cys Arg Lys Gln            335                 3 - #40                 3 - #45                 3 -        #50                                                                            - TCT TCC AAA CAT GCC CTG GGC TAC ACC CTG CA - #C CCG CCC AGC CAG GCC          1223                                                                           Ser Ser Lys His Ala Leu Gly Tyr Thr Leu Hi - #s Pro Pro Ser Gln Ala            #               365                                                            - GTG GAA GGG CAA CAC AAG GAC ATG GTG CGC AT - #C CCC GTG GGA TCA AGA          1271                                                                           Val Glu Gly Gln His Lys Asp Met Val Arg Il - #e Pro Val Gly Ser Arg            #           380                                                                - GAG ACC TTC TAC AGG ATC TCC AAG ACG GAT GG - #C GTT TGT GAA TGG AAA          1319                                                                           Glu Thr Phe Tyr Arg Ile Ser Lys Thr Asp Gl - #y Val Cys Glu Trp Lys            #       395                                                                    - TTT TTC TCT TCC ATG CCC CGT GGA TCT GCC AG - #G ATT ACA GTG TCC AAA          1367                                                                           Phe Phe Ser Ser Met Pro Arg Gly Ser Ala Ar - #g Ile Thr Val Ser Lys            #   410                                                                        - GAC CAA TCC TCC TGT ACC ACA GCC CGG GTG AG - #A AGT AAA AGC TTT TTG          1415                                                                           Asp Gln Ser Ser Cys Thr Thr Ala Arg Val Ar - #g Ser Lys Ser Phe Leu            415                 4 - #20                 4 - #25                 4 -        #30                                                                            - CAG GTC TGC TGC TGT GTA GGG CCC TCA ACC CC - #C AGC CTT GAC AAG AAC          1463                                                                           Gln Val Cys Cys Cys Val Gly Pro Ser Thr Pr - #o Ser Leu Asp Lys Asn            #               445                                                            - CAT CAA GTT CCA ACC ATT AAG GTC CAC ACC AT - #C TCC CTC AGT GAG AAC          1511                                                                           His Gln Val Pro Thr Ile Lys Val His Thr Il - #e Ser Leu Ser Glu Asn            #           460                                                                - GGG GAG GAA GTC TAGGACAGGA AAGATGCAGA GGAAAGGGGA AT - #ATCTTAGG              1563                                                                           Gly Glu Glu Val                                                                        465                                                                    - TACCATACCC TGGAGTTCTA GAGGATTCCT CGACAAGCTT ATTCCGATCC AG - #ACATGATA        1623                                                                           #  1639                                                                        - (2) INFORMATION FOR SEQ ID NO:6:                                             -      (i) SEQUENCE CHARACTERISTICS:                                           #acids    (A) LENGTH: 466 amino                                                          (B) TYPE: amino acid                                                           (D) TOPOLOGY: linear                                                 -     (ii) MOLECULE TYPE: protein                                              -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:6:                                  - Met Val Phe Leu Ser Gly Asn Ala Ser Asp Se - #r Ser Asn Cys Thr Gln          #                 15                                                           - Pro Pro Ala Pro Val Asn Ile Ser Lys Ala Il - #e Leu Leu Gly Val Ile          #             30                                                               - Leu Gly Gly Leu Ile Leu Phe Gly Val Leu Gl - #y Asn Ile Leu Val Ile          #         45                                                                   - Leu Ser Val Ala Cys His Arg His Leu His Se - #r Val Thr His Tyr Tyr          #     60                                                                       - Ile Val Asn Leu Ala Val Ala Asp Leu Leu Le - #u Thr Ser Thr Val Leu          # 80                                                                           - Pro Phe Ser Ala Ile Phe Glu Val Leu Gly Ty - #r Trp Ala Phe Gly Arg          #                 95                                                           - Val Phe Cys Asn Ile Trp Ala Ala Val Asp Va - #l Leu Cys Cys Thr Ala          #           110                                                                - Ser Ile Met Gly Leu Cys Ile Ile Ser Ile As - #p Arg Tyr Ile Gly Val          #       125                                                                    - Ser Tyr Pro Leu Arg Tyr Pro Thr Ile Val Th - #r Gln Arg Arg Gly Leu          #   140                                                                        - Met Ala Leu Leu Cys Val Trp Ala Leu Ser Le - #u Val Ile Ser Ile Gly          145                 1 - #50                 1 - #55                 1 -        #60                                                                            - Pro Leu Phe Gly Trp Arg Gln Pro Ala Pro Gl - #u Asp Glu Thr Ile Cys          #               175                                                            - Gln Ile Asn Glu Glu Pro Gly Tyr Val Leu Ph - #e Ser Ala Leu Gly Ser          #           190                                                                - Phe Tyr Leu Pro Leu Ala Ile Ile Leu Val Me - #t Tyr Cys Arg Val Tyr          #       205                                                                    - Val Val Ala Lys Arg Glu Ser Arg Gly Leu Ly - #s Ser Gly Leu Lys Thr          #   220                                                                        - Asp Lys Ser Asp Ser Glu Gln Val Thr Leu Ar - #g Ile His Arg Lys Asn          225                 2 - #30                 2 - #35                 2 -        #40                                                                            - Ala Pro Ala Gly Gly Ser Gly Met Ala Ser Al - #a Lys Thr Lys Thr His          #               255                                                            - Phe Ser Val Arg Leu Leu Lys Phe Ser Arg Gl - #u Lys Lys Ala Ala Lys          #           270                                                                - Thr Leu Gly Ile Val Val Gly Cys Phe Val Le - #u Cys Trp Leu Pro Phe          #       285                                                                    - Phe Leu Val Met Pro Ile Gly Ser Phe Phe Pr - #o Asp Phe Lys Pro Ser          #   300                                                                        - Glu Thr Val Phe Lys Ile Val Phe Trp Leu Gl - #y Tyr Leu Asn Ser Cys          305                 3 - #10                 3 - #15                 3 -        #20                                                                            - Ile Asn Pro Ile Ile Tyr Pro Cys Ser Ser Gl - #n Glu Phe Lys Lys Ala          #               335                                                            - Phe Gln Asn Val Leu Arg Ile Gln Cys Leu Cy - #s Arg Lys Gln Ser Ser          #           350                                                                - Lys His Ala Leu Gly Tyr Thr Leu His Pro Pr - #o Ser Gln Ala Val Glu          #       365                                                                    - Gly Gln His Lys Asp Met Val Arg Ile Pro Va - #l Gly Ser Arg Glu Thr          #   380                                                                        - Phe Tyr Arg Ile Ser Lys Thr Asp Gly Val Cy - #s Glu Trp Lys Phe Phe          385                 3 - #90                 3 - #95                 4 -        #00                                                                            - Ser Ser Met Pro Arg Gly Ser Ala Arg Ile Th - #r Val Ser Lys Asp Gln          #               415                                                            - Ser Ser Cys Thr Thr Ala Arg Val Arg Ser Ly - #s Ser Phe Leu Gln Val          #           430                                                                - Cys Cys Cys Val Gly Pro Ser Thr Pro Ser Le - #u Asp Lys Asn His Gln          #       445                                                                    - Val Pro Thr Ile Lys Val His Thr Ile Ser Le - #u Ser Glu Asn Gly Glu          #   460                                                                        - Glu Val                                                                      465                                                                            __________________________________________________________________________ 

What is claimed is:
 1. A method of treating benign prostatic hyperplasia in a subject which comprises administering to the subject a therapeutically effective amount of an antagonist which binds to a human α_(1C) adrenergic receptor with a binding affinity at least 691-fold higher than the binding affinity with which the antagonist binds to a human α_(1B) adrenergic receptor.
 2. A method of treating benign prostatic hyperplasia in a subject which comprises administering to the subject a therapeutically effective amount of an antagonist which binds to a human α_(1C) adrenergic receptor with a binding affinity at least 1089-fold higher than the binding affinity with which the antagonist binds to a human α_(1A) adrenergic receptor.
 3. The method of claim 1, wherein the binding affinity of the antagonist is at least 91-fold higher for the human α_(1C) adrenergic receptor than it is for a human α_(1A) adrenergic receptor.
 4. The method of claim 2, wherein the binding affinity of the antagonist is at least 28-fold higher for the human α_(1C) adrenergic receptor than it is for any human α₂ adrenergic receptor.
 5. The method of claim 1, wherein the binding affinity of the antagonist for the human α_(1C) adrenergic receptor is (I) at least 91-fold higher than it is for the human α_(1A) adrenergic receptor, (ii) at least 65-fold higher than it is for the human histamine H₁ receptor, and (iii) at least 229-fold higher than it is for the human α₂ adrenergic receptor.
 6. The method of claim 1, wherein the binding affinity of the antagonist for the human α_(1C) adrenergic receptor is at least 41-fold higher than it is for any calcium channel.
 7. The method of claim 1, wherein the binding affinity of the antagonist for the human α_(1C) adrenergic receptor is at least 234-fold higher than it is for a human histamine H₂ receptor.
 8. The method of claim 1, wherein the binding affinity of the antagonist for the human α_(1C) adrenergic receptor is at least 30-fold higher than it is for a human serotonin receptor.
 9. The method of claim 1 or 2, wherein the antagonist does not cause an orthostatis fall in blood pressure.
 10. The method of claim 9, wherein the antagonist additionally does not cause an orthostatic fall in blood pressure in rats at a dosage of 10 micrograms of antagonist per kilogram of rat.
 11. A method of inhibiting contraction of prostatic tissue which comprises contacting the prostate tissue with an effective contraction-inhibiting amount of an antagonist which binds to a human α_(1C) adrenergic receptor with a binding affinity at least 691-fold higher than the binding affinity with which the antagonist binds to a human α_(1B) adrenergic receptor.
 12. A method of inhibiting contraction of prostatic tissue which comprises contacting the prostate tissue with an effective contraction-inhibiting amount of an antagonist which binds to a human α_(1C) adrenergic receptor with a binding affinity at least 1089-fold higher than the binding affinity with which the antagonist binds to a human α_(1A) adrenergic receptor.
 13. The method of claim 11, wherein the binding affinity of the antagonist is at least 91-fold higher for the human α_(1C) adrenergic receptor than it is for any human α_(1A) adrenergic receptor.
 14. The method of claim 12, wherein the binding affinity of the antagonist is at least 28-fold higher for the human α_(1C) adrenergic receptor than it is for a human α₂ adrenergic receptor.
 15. The method of claim 11, wherein the binding affinity of the antagonist for the human α_(1C) adrenergic receptor is (I) at least 91-fold higher than it is for the human α_(1A) adreriergic receptor, (ii) at least 65-fold higher than it is for the human histamine H₁ receptor, and (iii) at least 229-fold higher than it is for the human α₂ adrenergic receptor.
 16. The method of claim 11, wherein the binding affinity of the antagonist for the human α_(1C) adrenergic receptor is at least 41-fold higher than it is for any calcium channel.
 17. The method of claim 11, wherein the binding affinity of the antagonist for the human α_(1C) adrenergic receptor is at least 234-fold higher than it is for a human histamine H₂ receptor.
 18. The method of claim 11, wherein the binding affinity of the antagonist for the human α_(1C) adrenergic receptor is at least 30-fold higher than it is for a human serotonin receptor.
 19. The method of claim 11 or 12, wherein the antagonist does not cause an orthostatic fall in blood pressure.
 20. The method of claim 19, wherein the antagonist additionally does not cause an orthostatic fall in blood pressure in rats at a dosage of 10 micrograms of antagonist per kilogram of rat. 